Yard and Garden: June 23, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for June 23, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Hosts: Mike Onnen, Manager for the Little Blue NRD & Donnie Engelhardt, Assistant Manager for the Little Blue NRD

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1.The first caller of the day wanted to know if it was time to spray for bagworms yet this year and what to use for bagworms?

A. Yes, the bags have emerged. There is time for a couple of weeks yet to get them sprayed, just make sure you spray before the bags are 1 inch in length for best control. You can use any general insecticide for controlling bagworms such as sevin, eight, bifenthrin, tempo, or Bt can be used for a safer control method. Bt will not harm bees and other beneficial insects.

Bagworm4

Bagworm

2. A caller has 2 large oak trees that when he parks his truck underneath it gets sticky from the aphids in the tree. What can be done to manage these?

A. The aphids are producing honeydew as an excretion and they do feed on the oak trees, but often this is not that damaging to the tree. You can spray for the aphids in the tree with a general insecticide, but if you give it a little time predatory insects will come in and kill the aphids. If you spray, you will kill the predators as well as the aphids. It is often not necessary to spray for aphids in a tree.

3. This caller has lilies that have grown too thick in her one garden bed. When can she divide these to transplant some in a new location?

A. This could be done this fall or you can wait and thin the lilies in the spring as well, either would be fine. I would advise against transplanting and dividing plants this time of year because in the heat, the plants don’t have enough roots to get to more water to keep them cool.

4. A caller has a weeping willow that has many leaves turning yellow and the tree is thinning. What would be wrong with the tree and how can it be managed?

A. This tree is likely dealing with environmental stress. There are not spots on the leaves to indicate a disease or damage that would be from insects. After viewing the photos, it is determined it could be due to improper planting as it looks too deep with no root flare. There may be stem girdling roots that would not be evident for a few years after planting.

5. How do you control ground squirrels in your yard?

A. There is a great publication on Ground Squirrels from the Internet Center for Wildlife Damage Management which shows how to set a trap for ground squirrels.

6. A caller has Iris, yucca, and prickly pear cactus that are all getting many weeds growing in and around these plants. The weeds include both grasses and broadleaf weeds. How can the weeds be controlled without injuring the desired plants?

A. The grasses can be sprayed with Grass-B-Gon or another similar grass herbicide. Unfortunately, there isn’t a selective herbicide that will kill broadleaf weeds and not kill broadleaf desired plants. For the broadleaf weeds, the best defense is to hoe the weeds out and mulch the garden in the future to hold the weeds back.

7. This caller has a plum hedge that has holes in most of the leaves throughout the hedge. The holes form initially as a brown spot and then a hole appears. What would cause this?

A. This is likely due to herbicide drift. There is no control for that, but if it is minimal it shouldn’t impact the hedge too much. However, multiple years of herbicide drift to the same plants can start to stress and in some cases kill the plants.

8. A caller has onions that have formed a soft, brown spot on the onions when they were dug recently. What would cause this?

A. This is likely a rot issue that developed from a pathogen in the soil. It is always best practice to rotate the crops. Also, ensure that you properly cure your onions before storage.

9. How can you control sandburs?

A. Crabgrass control in the spring will work for sandburs as well as foxtail and crabgrass. All of these are annual grasses.

10. A caller has tried to plant roses in the same location for a couple of years now and it seems like they grow to about 18 inches, bloom, but then die over the winter months. The are planted in a garden with rock mulch, watered with a bucket of water as needed, and were pruned off in March. Why can’t the caller get the roses to live longer than one year?

A. This sounds like mostly environmental stress to these plants. Rock mulches are hot and absorb no water, switch to a wood chip mulch to cool the roots and hold moisture. Watering should be done with a soaker hose or other type of sprinkler system. When a bucket of water is poured over the plants as needed, the water fills up the top pores of the soil surface quickly and then spread out rather than down. A slow trickle on the plants for a while each week to wet the soil down to about 6-8 inches will be more beneficial. Pruning of roses is best done in the middle of April once growth has begun further to ensure healthy wood is not also removed with the dead wood too early in the spring. Add extra mulch around the plants in the winter months, up to 4-6 inches deep in the winter months, then spread the mulch out to 2-3 inches deep during the growing season. Extra mulch in the winter will help protect the plants from inconsistent temperatures in the winter.

11. This caller wants to know when to dig up garlic? He also wants to know if bleeding hearts can be cut back now?

A. Garlic should be harvested in July after 30-50% of the leaves have died back. Harvest during dry weather and leave the bulbs on the ground to dry for a week before storing. The flower stalks of bleeding hearts can be removed, but the leaves need to be left on the plants to build sugars for next years growth and flower production.

12. How can grasshoppers be controlled if they are in the flower garden?

A. Any general insecticide will work for grasshoppers in flower gardens. Sevin, eight, tempo, bifenthrin, and others will work for flowers. When treating grasshoppers, it is also important to treat the grassy areas of roadsides and ditches where grasshoppers are often found.

13. This caller has grass growing in his asparagus patch. How can the grass be controlled?

A. Hand pull and apply a mulch to the asparagus patch. The earlier you get the mulch applied in the season, the better the control will be. Also, after harvesting is complete, the asparagus can be snapped off below ground level and Roundup or another glyphosate product can be applied as long as there is no green asparagus above the ground.

 

Grasshoppers, J. Larson

The four main pest species of grasshopper in Neb. Top row two striped grasshopper adult, red legged grasshopper adult. Bottom row differential grasshopper adult, migratory grasshopper adult.

14. How can you control grasshoppers in the vegetable garden?

A. Sevin, eight, and bifenthrin are labeled for use in the vegetable garden. Also, remember to treat for grasshoppers in tall grasses along roadsides and ditches. Follow the PHI (pre-haravest interval) to know how many days after application necessary to wait to harvest the vegetables.

15. A caller wants to know when to transplant peach trees?

A. Fall or spring are both good times to transplant any trees.

16. The final caller of the day has a pond with moss or duckweed in it making it cloudy. What can be done to clean up the water?

A. Avast SRP is labeled for Duckweed and Copper sulfate can be used for Algae.

Yard and Garden: June 16, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for June 16, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Jim Kalisch, Insect Diagnostician from UNL Extension

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1. The first caller of the day has a Daylily that has yellow streaks on the leaves. What is causing this? She also has Roses that are getting yellow leaves and sprayed a rose product containing both an insecticide and a fungicide. Will this work for the roses?

A. The daylilies likely have Daylily Leaf Streak, a fungal disease common on daylilies. It would be best to remove the infected leaves and destroy them from the plants as you see them and clean up the plants in the fall by cutting off all the foliage and destroying it for winter. It will also help to water from below the plants rather than using an overhead sprinkler. Also, it sounds like her daylily plants are overgrown, this fall it would help to dig and divide them to increase air space. As for the roses, they could be dealing with black spot or rose slugs. The fungicide and insecticide combined product will work to reduce the incidence of both of these problems.

2. A caller wants to know when the best time to transplant asparagus and what can be done for a cypress tree turning yellow?

A. Asparagus is best planted and transplanted in the spring. However, if this is an old patch of asparagus, it would be better to just start from new crowns. Either way, you need to wait 3 years to harvest to allow the roots to develop. Trees that turn yellow instead of their deep green color through the growing season are often lacking iron. The best management for Iron chlorosis is to use a trunk injection of iron. However, with cypress trees, it is often difficult to get them out of this condition and multiple years of trunk injections can start to stress the tree out to the point of death in some cases.

3. This caller has peonies and moonflowers in her yard and wants to know when the best time is to transplant them and how to prepare the area that was rocked to get these plants to grow well?

A. Spring will be best for establishment, but fall would be a second best option to transplant these plants. Remove the rocks that were in the new location and then till the soil, adding compost in as you till to improve the structure of the soil and add some nutrients back into the soil. When moving peonies, make sure that it is planted at the same depth in the soil, to deep and the plants will not flower. After you have planted, add some wood chip mulch around the plants to help them stay cool and hydrated. Water as needed.

4. A caller has a large blue spruce that has some browning on the needles and those needles are beginning to fall off the tree. This has started at the bottom of the tree and is moving upward through the tree. What is causing this? Can her tree be saved?

A. This could be one of two things, either a fungal disease or spidermites. After discussion, the caller stated that the needles are more of a reddish brown, which is distinct for a fungal disease called Rhizosphaera, which is common now. The trees can be sprayed with a fungicide to reduce the spread of the disease. Over time, the trees will grow new needles.

5. This caller recently planted 2 new 7-feet tall blue spruce trees. They are watering these trees at least once a week for 30 minutes and they are mulched in with straw. Now, the lower branches are droopy and wilted. Do these branches need to be removed?

A. These trees are dealing with transplant shock and need some time to build some new roots and get over the shock. Leave the branches for now and continue to water as needed.

6. A caller has a volunteer tomato plant that is about a foot tall. Can it still be transplanted now to be grown in the garden?

A. Yes, it will still be fine. The volunteer tomato will not come true from seed, so it may not be the same type of tomato as what was planted last year, but it should grow fine.

7. A caller has a bald cypress that has needles that are curling. What would cause this?

A. This sounds like drift from 2,4-D or another type of herbicide. This would happen if people are spraying these herbicides now that the temperatures have risen so high. Slight damage may be only aesthetic this year. Multiple years of damage can start to cause stress and even death to the tree.

8. This caller is growing grapes in his backyard. These grapes have black spots on the vine that the caller sees most years. The grapes then shrivel up before they can be harvested. What would cause this?

A. This sounds like a fungus. It would be best to get on a fungicide schedule with your grape plants to keep this fungus from returning every year. For more information on when and what to spray, view the Midwest Small Fruit and Grape Spray Guide

9. How do you stop zoysia grass from spreading in Tall Fescue and Kentucky Bluegrass?

A. Fall fertilization will push zoysia to grow when it is going dormant because it is a warm season grass. This fertilization will be beneficial to the cool season grasses.

10. A caller has Canna bulbs. Is it too late to plant them yet this year?

A. They can plant them to keep them alive and get sugars built up for next year, but they will likely not bloom this year. Cannas have to be dug up and stored indoors over the winter and if they are left out of the ground for 2 seasons, they may not have enough energy to grow after that. Planting the bulbs this year to get sugars for growth next year would be the best place for them to be stored.

11. This caller has patches of round grass in the lawn. How can it be controlled?

A. This is likely a perennial grassy weed such as windmill grass, orchardgrass, or quackgrass. These can be controlled with roundup and then overseeding or with a mesotrione product such as Tenacity. For more information on these weeds, view this article from Lancaster County Extension.

12. A caller has a spirea bush with dead wood in it. Can it be cut back now?

A. Yes, this isn’t the best time for a summer blooming spirea, but it will be fine. Summer blooming spirea’s should be pruned in the late winter, such as February and March for best blooms. This can be pruned back to 6-8 inches from the ground. However, if it is a 50 year old plant, as the lady stated, it may be getting old and may not return from a rejuvenation cutting as it may be dying due to old age.

13. How do you get rid of poison ivy which is growing in rose bushes?

A. It will be difficult to remove the poison ivy and not harm the roses or not get a medical reaction from the poison ivy while working to remove the posion ivy. Paint roundup on the leaves of the poison ivy now, being careful not to get the glyphosate on the roses. It may take multiple applications to kill the poison ivy entirely. Wear long pants, long-sleeved shirt, gloves, socks, and shoes when applying this to avoid getting a rash from the poison ivy.

Poison Ivy-David J Moorehead, Univ of GA, Bugwood

Photo of Poison Ivy courtesy of David J. Moorhead, University of Georgia, Bugwood.org

14. This caller has a trumpet vine that is creeping into the lawn. How can it be controlled in the lawn without damaging the parent plant?

A. Just keep mowing it off. These are likely runners from the main plant and if a pesticide is used to control the runners, it will go through the plant into the roots of the main plant.

15. This caller is curious if poison ivy oils can transfer to pine cones on the ground surrounding the poison ivy plants? She is also curious if she can trim her Iris plants back now or if she has to wait until the fall?

A. According to Clemson University, the poisonous oils can remain active for months on objects. It can be picked up on tools, clothing and the fur of pets. Anything that may carry the oil should be carefully washed. Even dead plants or roots may cause allergic reactions for a couple of years. So it is best to clean the pine cones that came in contact with the poison ivy. For more information, see this guide from Clemson

As for the Iris plants, you need to wait until fall to cut the leaves back when the leaves turn brown for the year. It gives the plant time through the summer to build up sugars to help bloom early next spring.

16. What type of tree would be recommended that is smaller but provides good shade?

 

A. Dwarf Chinkapin, Pawpaw, Redbud, Crabapple, Serviceberry

Yard and Garden: June 2, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for June 2, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Graham Herbst, Community Forester from the Nebraska Forest Service

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1. The first caller of the day has a Hen and Chicks plant that has grass growing in it. What can be done to remove the grass? She also has spiders in her lawn, what can she do to control them?

A. Grass-B-Gon is a product that contains the active ingredient Fluazifop. This is a grass herbicide. This product or any others containing Fluazifop can be sprayed directly over broadleaf plants with no damage to the desired plant. The spiders are not an issue outside in the lawn, in fact, they are beneficial. Spiders in the lawn are feeding on insects, many of which cause problems to our plants or bother us. Outside, spiders are beneficial. To keep them from coming indoors, home barrier sprays or tempo can be used around the foundation of the house to keep spiders and insects outside. If there is a fear of spiders, the tempo could be used where the spiders are seen.

2. A caller has a mock orange that has not bloomed for the past few years and now this year it finally is blooming some. Should it be removed? Why hasn’t it been blooming?

A. This could be due to a maturity issue. Many of our woody plants need to become established and get to a certain age before they will begin blooming. It could also be due to pruning time. Mock Orange bushes need to be pruned right after they finish blooming because they bloom on last years growth, or old wood. If they are pruned in the fall or early spring, the blooms would be cut off.

3. When is the proper time to spray for bagworms on blue spruce trees?

A.Spray when the bags are small to get the best control. It is best to spray after the bags emerge in the late spring to early summer but before the bags get longer than 1 inch in length. Mark a branch with a bag on it now and keep checking it to determine when the bags have emerged.

4. A caller has 6 table grape plants that had grapes set on. Now the grapes are dropping off and 70% are gone from the plants. What has caused these plants to loose all of the grapes?

A. This could be due to frost damage. Here is a guide from Oregon State University to describe the many factors that can hinder fruit development in grapes.

Forsythia-Richard Elzey, Flickr

Forsythia, Flickr image courtesy of Richard Elzey per CC license

5. Is it too late to prune forsythia this year?

A. It is too late to prune and not cut off any blooms for next year. Spring blooming shrubs should be pruned shortly after they finish blooming for the year. Forsythias bloomed in March this year, so it would already be starting the formation of flower blooms for next year, pruning them now would cut those buds off. If the intent is to just prune a few branches just a little, it wouldn’t impact the overall blooming of the shrub, but pruning too heavily will lead to little or no development of flowers.

6. A caller wondered where they could go to find the wrap around water bags for trees?

A. Local nurseries should carry them or there are many online locations where you can order them. These bags are beneficial to help keep the root ball moist to help get new trees established.

7. Can Grass-B-Gon be used in strawberries or phlox and will preen reduce the number of runners grown off of strawberry plants?

A. Grass-B-Gon is not labeled for use in fruit bearing tree crops and vines. So, it cannot be used in strawberry plants. It would be good to use for grasses growing in phlox and not cause any harm to the phlox. Preen stops the germination of seed to reduce weeds grown from seed in the garden, so it will not harm runners which are growing off an existing plant, not from seed. Check to make sure the preen you are using is labeled for use in strawberries, the general preen is not for use in vegetable gardens.

8. How do you transplant a wild rose?

A. First, make sure it is on your property. Then, just make sure you dig up as much of the rootball as possible and replant it right away. You could also try taking a cutting from one of the branches and dipping it into rooting hormone and placing it into a pot of gravel to get roots to grow. Once roots develop, you can plant the rose.

9. A caller wants to build a privacy border with shrubs. Would Burning bush work for this or are there other options to choose from?

A. Burning bush would be a great privacy wall with good fall color. Other shrub choices would include serviceberry or any of the viburnums. You could plant it now, just make sure the plants get plenty of water with it being this hot and the roots being minimized due to transplanting.

10. This caller has tomato plants that when they planted it they saw grubs and wireworms in the soil around it. Should they treat for this and if so, what should be used?

A. Grubs are not controlled effectively around vegetable gardens because the chemicals with the best control are not labeled for use in the vegetable garden. However, there is a fairly high threshold of grubs and wireworms in the garden before damage is too high. A few grubs or wireworms throughout an entire garden will not cause any real damage. The plants they are most problematic on would be the root crops such as potatoes.

11. This caller had 2 questions: Her asparagus has been planted in this location for 30 years and is quite spindly, why is that? Her peonies are done blooming now, can she deadhead the spent flowers?

A. The asparagus is regularly fertilized so the small spears could be due to heavy harvest or it could be getting old or too crowded. It would be time this year to stop harvesting to allow the plants to recover and make sure to stop sooner next year. Once peonies and iris plants have completed their blooming period, the flowers can be cut off and composted. Leave the leaf material on the plant to build sugars to help with the flowering next spring.

12. How do you control weeds in asparagus?

A. Hand pulling and mulch would be the best options for weed control. When the plant is done in the fall and the leafy material is all removed below the ground level, the existing weeds can be sprayed with Roundup as long as no green material from the asparagus is above ground or showing. Here is a good explanation from Backyard Farmer of why we don’t use salt on asparagus for weeds and how to effectively control weeds with Roundup.

Carpenter Bee, J. Kalisch

Carpenter Bee photo from Jim Kalisch, UNL Entomology

13. A caller has carpenter bees digging holes into the roof of a patio. What can be done about this?

A. You can plug those holes with caulk or putty or use a sevin dust in the holes. For more information on Carpenter Bees, see this article from Retired Extension Educator, Barb Ogg

14. This caller has puncture vine in the lawn. What can be used to control it?

A. 2,4-D is a good way to control it in the the spring before it blooms.

15. A caller has peonies that need to be transplanted. Can they also be divided when they are transplanted?

A. Yes, they can be cut into a few pieces when they are transplanted this fall. Just make sure that each section you cut off the plant has 3-5 eyes which are more like pink noses or knobs on the roots of the plant. Peonies are best transplanted and divided in September or October.

Yard and Garden: May 19, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for May 19, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Jim Kalisch, Insect Diagnostician for Nebraska Extension

If you enjoy reading my Q&A from the show each week, take my quick survey at: http://go.unl.edu/44qr and be entered to win a free plant book or some free UNL gifts.

1. The first question of the day was from a gentleman wondering how to tell when to water his self-watering containers? There is no viewer or gauge to show the water level on the outside of the container.

A. Because a self-watering container is continually watering the plants in it, it can always be refilled. In this case, this container will keep your plants watered for at least a week to two so, they should be refilled before they completely dry up. I would suggest refilling the reservoir every week to 10 days.

Bagworm4

Bagworm

2. A caller has bagworms in their cedars. What is the best way to see them before they get too big to treat?

A. They haven’t hatched yet this year. Mark the branch you have a living bag on with flag tape to check the same bag every week from now until they hatch. You can also place a few bags in a container and keep it in the tree to see when they hatch in the container. Wait a couple of weeks after the initial emergence to ensure that all of the bagworms have hatched before spraying. The bags in the shade will take longer before they hatch. Once they have hatched, Bt is a good insecticide to use when they are young or you can use a product containing bifenthrin in it for longer lasting control.

3. This caller is wondering what types of problems we can expect in the garden, lawn, and trees this year due to the excess rain?

A. The rains in the spring tend to lead to more fungal diseases this time of the year, but they are not terribly harmful and many should fade out as the summer heats and dries up. Many things to watch out for would include fungal diseases in the lawns and trees. We are already seeing Peach Leaf Curl, different fungi in blue spruces, anthracnose on the leaves, and mushrooms popping up in our lawns. We will also see more problems from earthworms and fungus gnats which are mostly nuisance problems.

2015-09-22 18.45.39

Squash bugs on a zucchini

4. How do you effectively control squash bugs in the vegetable garden?

A. Squash bugs are difficult to control in our cucurbit vegetables including zucchini, squash, pumpkins, gourds, melons, and cucumbers. The best option is to kill the adults when they first emerge to manage the population before it explodes. Watch for the eggs as they develop on the underside of the leaves to destroy them before they emerge. Switch to other chemicals for management besides just using “Sevin” for control, which they are becoming resistant to. There are also lures that can be used for them which might help early in the season.

5. A caller has an Oregon Trail Maple that leafed out early this spring. Now the leaves are slightly cupped and turning yellow along the edges. What would be causing this?

A. This sounds like frost damage. If the leaves came out early, they may have been nipped by a light frost in late April. We are seeing this problem throughout many trees and shrubs this spring. The leaves may drop entirely from the tree, but the tree will then push secondary buds to produce new leaves that are not injured.

6. This caller wants to know how to propagate a lilac and a hydrangea.

A. For lilacs: A cutting can be taken from the shrub. Cut off a small, pencil-sized, branch and place it into rooting hormone than plant it into a pot of gravel that is kept moist. Once roots have formed, the plant can be transplanted into the ground. They can also be propagated through a process called layering which is where you bend a flexible branch down to the ground and plant it to allow roots to form on the branch while it is still attached to the main plant. Once roots form, cut it from the parent plant and transplant it. There is more information on this in the NebGuide: Lilacs

Hydrangeas can also be layered to produce new plants or they can be divided. It is too late to do the division this year, but early next spring you can dig up the plant and use a spade to divide the main plant and replant the pieces. Depending on the side you can get 2-4 pieces from a divided plant.

7. Is cedar-apple rust damaging to cedar trees?

A. Cedar-apple rust shows up in the spring on cedar trees as a orange, slimy, ball with horns. This is the gall that opens up with rains in the spring. Cedar-apple rust is not harmful to the cedar tree, it just uses the cedar trees as an alternate host through the winter. When these galls are seen on the cedar, that is the time to spray any susceptible apple, crabapple, pear, or hawthorne tree to avoid damage to them. For more information view this NebGuide

8. This caller has a pink peony that hasn’t bloomed well this year. There is some discoloration and fuzzy appearance to the leaves and buds. What would cause that?

A. This sounds like botrytis blight, a common fungal disease to our peonies. It is not very harmful to the plant itself, so it is not necessary to control it. In the fall, make sure you remove and destroy all of the plant material to reduce the spread to your plants next spring.

9. A caller has a Chanticleer Pear with leaves that have black spots on them and the top isn’t leafing out this spring. What would cause that?

A. This could be due to frost damage as well. Or check the tree for oozing sap along the trunk or branches. The damage could be from borers. It might also be from fireblight which would cause the leaves to turn black on some branches where the end of the branch hooks over like a shepherds crook. Fireblight is likely since this showed up in the tree last summer. If it is fireblight, prune out the infected branches and dip your pruners into a bleach water solution in between the cuts.

10. This caller has roses that had dieback from the winter. She pruned them off in early April and now it looks like the only live growth is coming from the ground. What is wrong with her roses and will they come out of it?

A. Unfortunately, these roses seem to have more dieback from the late frost we saw in April. If there is no green growth showing up on the main part of the plant, it is likely that it has died back. The roots would be shooting the new growth from the ground, but that is not going to be the same type of rose that you had there before because our roses are often grafted. The growth from the ground would be from the rootstock so it wouldn’t be the size and color of rose that was originally purchased. Unfortunately there is nothing that can be done about that. It might be time to go and choose some new rose colors for your garden.

11. A caller has a river birch tree that dropped its leaves in the summer last year. The leaves now are yellow and only the top half of the tree has leafed out this spring. They are 20 year old river birch trees. What would be causing this problem?

A. Look on the branches of the tree for signs of bronze birch borer. Some of the signs of this borer would be rippling on the branches or holes in the stem or branches. If you find the signs of bronze birch borer, you can treat it now with a borer spray or with a systemic insecticide.

12. A caller has a river birch tree that was growing in a clump and one of the trunks of the group died out. Should it be removed now?

A. Yes, any dead part of a tree should be removed as soon as it is noticed. A large part of a river birch, like this, could be hazardous if left standing after it dies. Unfortunately, when that branch is pruned off decay will likely begin but there is no way to prevent that at this point. This will likely be a large portion of the tree removed and that large of a pruning cut may not ever heal over entirely. When a branch doesn’t seal up, decay can get into the tree causing more damage. We don’t advise painting the stump with anything.

13. A question came in via email regarding a red twig dogwood. This dogwood is 4-5 years old and has never been pruned. Following the storms this week, some branches are falling over blocking a mowing path. Can those be pruned now? What should be done with it in the future?

A. Broken branches can be removed at any time. If these are just bending over, they could still be removed if necessary, but they may pop back up to their normal standing position. For future, red twig dogwoods should be pruned to the ground every 3-5 years to maintain that good red color on the twigs. They should be pruned in the late winter to early spring.

14. A lady called who has a Cranberry Bush Viburnum that has dead branches in it. Can those dead branches be pruned out now?

A. Yes, dead branches should always be removed when they are noticed. Check to ensure that these branches didn’t die due to Viburnum borers, if so, treat with a borer spray or systemic insecticide.

15. The last caller of the day has 2 different plants that have problems. A maple tree has brown specks on the leaves and they are falling off the tree. A Peony bush has leaves that are turning yellow along the edges of the leaf. What would be causing these two problems?

A. These both sound like frost damage. They will both be fine. The maple may drop all the damaged leaves and put on new growth.

Yard and Garden: May 12, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for May 12, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Dr. Paul Read, Viticulture Specialist from UNL

1. The first caller of the day called to ask when is the best time to take cuttings from grape vines and how should it be completed?

A: To take a cutting, when you cut off the dormant growth from the previous year, you can take those branches and put them in moist sand to get them to root. After the last spring frost of the year, you can plant those rooted branches outdoors. When you do this method, you need 2-3 buds on each branch. Put at least 1 bud into the ground and have 1-2 buds out of the ground for leaf growth. At this time of the year, you can complete the layering method of propagation. For layering, just bury a few of the longer branches that are still attached to the vine. Once they root, you can cut them from the main plant and replant somewhere else.

2. A caller has a 7 year old peach tree that is dropping leaves like it is fall. What would be causing this to happen and can it be corrected?

A: This could be abiotic stress due to unfavorable environmental conditions. It could also be from peach tree borer. Look along the trunk for small borer holes or sap oozing from branches or the trunk to know if it is the borer. If borers, spray the trunk with a fruit tree insecticide spray. If it doesn’t seem to be from insects, keep the tree healthy through a good mulch ring and regular watering as needed when natural rains are infrequent.

3. This caller has 2 concord grapes that were producing well last year but were taken by the birds before they could be harvested. How can you keep these birds away?

A: Bird netting over the plants to keep the birds out is the only good, effective method of managing birds in grapes.

This caller also wanted to know what is wrong with her peach trees? She has 2 peach trees that are 9-10 years old that now have an orange sap oozing from the trunk.

A: This would be from gummosis, a fungal disease common on peach trees. There is no real cure for this disease, it is just best to prune out the small branches that are affected and cut 6-8 inches below the infected area. Dip your pruners into a bleach/water solution between cuts to prevent further spread of the disease. It could also be from peach tree borers. In that case, use an insecticide labeled for use on peaches for borers.

4. A caller has a row of cottonwoods but there is one tree in the middle that always has yellow leaves rather than green leaves. What is wrong with it and can it be corrected?

A: This is most likely due to an iron deficiency in this tree. That can be corrected by having a certified arborist come in to do a trunk injection. The granules or stakes around the tree are not very effective. Often, iron chlorosis is a sign of other problems with the tree and may be the beginning of the end for the tree. That being said, many of our trees live many years after developing an iron deficiency and some just need an iron injection every 5+ years to live a long and happy life.

Tree hole for blog

Photo of the damage occurring to the Maple tree.

5. A caller has some maples that were recently pruned and the branches had a fungus and some white powdery substance in them when the branches were removed. What is wrong with them and do they need to be removed?

A: This caller emailed me with photos of the problem so I could see for sure what is wrong with the plants and if it can be corrected or if it is a safety issue. Unfortunately, this does look like decay in the tree. Decay within the interior of the tree can be dangerous for when it may fall, the tree is not stable when it has decay. I would guess that the tree has a large limb that was removed at one time and it was too big or improperly cut and now there is a large hole leading into the tree. I would get a certified arborist out to take a look and possibly remove the tree.

6. This caller has a cedar windbreak and would like to plant crabapples. Can crabapple trees grow near a cedar tree?

A: Yes, you can plant crabapple trees near cedars, just make sure that you select a variety that is resistant to cedar-apple rust to avoid having to spray annually to avoid the damage from cedar-apple rust.

7. A caller has a blue spruce tree that is 8 feet tall and was planted 14 years ago that died over the winter months. What happened and how can it be avoided in the other trees in the row?

A: This could be due to a canker which is a fungal disease that stops the flow of water and nutrients from the canker point outward and upward through the tree. If the canker occurred on the lower part of the trunk it would cause the tree to die. There is no cure for canker and no way to prevent it. It could also be due to a root issue that could have happened when the tree was planted or in the nursery. The tree may have a root that girdled the stem killing the tree or it may have been planted to deeply. When you remove the tree, look at the root system to see if this was the problem.

8. This caller has small brown circles in the lawn all around a tree. This problem occurs every year later in the summer in the same location of the lawn. What would be causing this and can it be controlled?

A: This is most likely due to summer patch, a common lawn fungal disease that occurs in the mid-late summer. Normally, this isn’t something that is treated for because it doesn’t occur in the same location every year, but for this caller, it does. Management practices in the lawn can help, such as mowing higher and doing core aeration to reduce the thatch layer in the lawn. If necessary, fungicides labeled for summer patch can be used from now until the end of June.

Summer Patch, L. Giesler turf update

Summer Patch in Kentucky bluegrass photo by Loren Giesler, UNL Plant Pathology

9. What is a better species selection than using Bradford pear?

A: Chanticleer or Cleveland Select are better options for pear trees than a Bradford Pear. Bradford pears tend to have narrow branch arrangement that leads to more broken branches from high winds and storms. These two options are better choices because their branches are wider when arranged on the trunk.

10. A caller has a maple tree that is half green and half a much lighter green color. What would cause this and can it be corrected?

A: The soil pH is higher on one side. A disturbance on the one side could cause it to have iron deficiency on the lighter green side. Try to spray chelated iron on the lighter green side to fix the problem.

11. When is the best time to start asparagus?

A: Spring is the best time, from March to April is prime time for planting asparagus crowns. Be sure to still wait 3 years before full harvest begins.

12. The final caller of the day had 2 questions. She had botrytis on her strawberries last year and sprayed a week ago. Does she need to spray again? Also, can an Annabel Hydrangea be planted in full sun?

A: For the strawberries, apply from 5-10% bloom until flowers have finished blooming. For more information see the Midwest Small Fruit and Grape Spray Guide from Midwest Universities including UNL. Annabel Hydrangea is one that prefers partial shade. I would avoid planting it in full sun on the South or West side of a building where it would get too hot.

 

Yard and Garden: April 28, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 28, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Dick Campbell, Owner of Campbell’s Nursery in Lincoln, NE

1. The first caller of the day has a Lilac that has bloomed in the past, but it isn’t blooming much. It has never been a reliable blooming shrub. What is wrong with it and how can it be fixed?

A: This plant was bloomed a few times in the fall, which would cut off the blooms for the following spring. However, this isn’t the only problem because for the past couple of years they have been better at timing their pruning. A late frost could have hit the blooms causing problems with bloom, it may reduce the overall bloom amount. Also, this could be a nutrient issue. A good fertilizer, such as bone meal, could be incorporated into the soil surrounding the plant to help with the nutrient availability.

2. A caller has ribbon grass that has died out in the center. This dead center has continued to get larger over the years. What can be done about that?

A: This plant needs to be divided. Many perennial grasses will develop a dead center when it is time to dig them up and divide them. The spring is a good time to do this for grasses. Iris plants will do this as well, they are best divided and replanted in the fall.

3. This caller has a weeping Norway spruce that is bending over heavily. Should it be trained to keep it more upright?

A: This is a typical growth habit for a weeping Norway spruce. They bend over more than some of the other weeping varieties. It would be good to put a small stake along the trunk of the tree to support it for more upright growth.

This caller also wanted to know what the timing was for spraying apple trees for Cedar-Apple Rust?

A: Now would be a good time. When the galls on the cedar rust have come out to look like a slimy glob in the spring rains it is time to spray. Those galls have just begun to open up and release the spores. For more information on cedar-apple rust, see this NebGuide.

Photo of Cedar Apple Rust Gall photo courtesy of Mike Lewinski via Flickr Creative Commons License

4. A caller has a cherry tree that has a split going up it and now it has sawdust around it on the ground.

A: Often we see insects in our plants as a secondary problem. What you are dealing with here, is most likely carpenter ants. They have come into the split in the tree and are making a nest in the rotting heartwood. The carpenter ants are not doing any more damage to the tree than what is already done. They can be killed by using an insecticide dust in the tree crack, such as sevin. However, the more concerning issue is the crack in the tree. If the tree is very large it may be a hazard. Tree removal may be necessary. If the crack is not very deep, it could be a frost crack which would be less hazardous.

5. Can you grow English Walnuts in Nebraska?

A: Yes, they can be grown here, it is most likely you will have to plant them from a seed as there aren’t many grown as plants for sale. Check with the Nebraska Nutgrowers Association for more information and seed/plant sources.

6. This caller has a blue spruce that is not growing well. It was planted 17 years ago and hasn’t grown more than a couple of feet in this time. What is wrong and can it be fixed?

A: The tree could be battling with too much brome grass growing around it and competing for nutrients and water. It would be beneficial to kill the brome grass and to add a mulch ring of 2-3 feet out and 2-3 inches deep around the tree to help reduce competition. This also could be a root issue that there would be no fix for. Often times, our trees are planted too deeply or grown in a container too long causing the roots to circle the tree. Once the tree is planted, there is no way to fix these conditions and the damage may not be present in the tree for 10-15 years after it was planted. This could be the case with this tree. Try adding mulch and ensuring proper irrigation through the growing season and it may come out of it.

7. A caller has a redbud that is 8 years old. The branches are dying and there are holes in the trunk. It seems that only one branch is still alive on the tree. What can be done for the tree? Or should it be removed?

A: The holes could be from borers that can be treated, but are often a secondary pest. If only one branch is left alive on the tree, it may be time to replant.

8. This caller is planting a new garden in an area that was a cornfield until this year. What do they need to do to the soil to plant in it?

A: Because this has been used as a crop field, I would advise a soil test to see where all the levels of pH, organic matter, Nitrogen, Phosphorus, and Potassium are at and to ensure vegetable crops will even grow in the soil that has been heavily planted for many years.

9. A caller is cleaning out dead and dying pine trees in a windbreak. Do the stumps need to be removed? What can be done to get it ready to replant?

A: If they are Junipers, or eastern red cedars, they can simply be cut off at ground level and they will not regrow. With some of our windbreak plants, they may need a stump treatment of 2,4-D or Roundup or a mix of the 2 products. If you are planning to plant a new windbreak where you removed these plants, it would be beneficial to grind out the stumps. If there is enough space, you can replant around the old stumps, just stay a few feet away from the stumps left behind if you don’t remove them.

10. What is the best care to give to seedling trees given to students for Arbor Day?

A: Grow the seedling in a pot for a year. When winter comes either plant the pot in the ground with heavy mulch or bring the container into the garage. Next spring, plant the seedling into the ground and protect it with fencing from rabbits and deer.

11. A caller wants to know how to control sandburs and where you can purchase milkweed plants?

A: Sandburs are controlled with crabgrass control products. As a preventer, using crabgrass pre-emergent herbicides will also prevent the germination of sandburs. If they have already germinated and are starting to come up, you can use a post-emergent herbicide for crabgrass such as quinclorac or Drive or Dimension. You should be able to find Milkweed plants at many local nurseries.

12. This caller has a white powdery substance on her peonies. What is it and what can be done for it? Also, she has a cherry tree that was severely damaged from deer, but now there are new suckers growing from the ground around it. Can those cherry tree suckers be grown into a new tree?

A: The white substance on the peonies would be powdery mildew. It is not very harmful to the plant. You can use a fungicide on it to control the spread of the disease. Also, make sure you cut off and remove the above ground growth that dies back in the fall to reduce the spores that overwinter for next year. The cherry suckers may not come up as the same species as you had planted and they may not be strong growing. Many of our fruit trees are grafted for a strong root system but desired traits from other trees. When suckers grow from the roots, you only get the type of tree that the main root system was and not the more desirable traits from the above ground portion of the plant. You can try it if you have room, but otherwise it would be best to start over from a new tree.

13. A caller put preen on his garden earlier this spring to stop the weeds. Now he is concerned if the plants he starts from seed this year will grow?

A: Unfortunately they will not grow where the preen is without extra care. You can either plant these plants from transplants or as seed in another location or in pots or you can till the bed to destroy the preen that is working as a barrier in the garden. Once you have gotten seeds to start growing in the garden, you can reapply the preen to reduce weeds later in the season.

14. A gentleman has holes around his house that are 1.5 inches in diameter and his tulip bulbs have been eaten off. What would cause these holes and how can the “critter” be managed?

A: This could be from either 13-lined ground squirrels or from voles. If it is voles, there would be runs in the lawn. Place a couple of snap-type mouse traps perpendicular to the runs in the lawn to manage the voles. If it is 13-lined ground squirrels, see this publication from UNL.

Yard and Garden: April 14, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 14, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: George Pinkerton, Director of Landscape Maintenance at Downtown Lincoln

1. The first question came from a caller wondering what the timing is for crabgrass preventer?

A: Typically we go with mid-to late April for application of crabgrass preventer. Crabgrass germinates when soil temperatures reach 55-60 degrees Fahrenheit. In most of the Southeast Nebraska area, we have just recently hit that. Anytime in the next couple of weeks would be fine to apply your crabgrass preventer. It might be best for control to apply a split application this year. For a split application, apply half of the recommended rate now and the other half of the recommended rate 8-10 weeks later. The split application will give you a longer season of control for crabgrass and other annual grassy weeds.

2. A caller was wondering about their gladiolus bulbs. They have had problems with thrips insects in the past and they had heard they should soak their bulbs in lysol to control them. Is this a good method of control or is there something better?

A: As it turns out, you can soak the corms in a solution of lysol water prior to storage of the corms over the winter months, according to the University of Minnesota Extension. You can also dust the corms with a sevin dust prior to storage in the late fall, store them with mothballs, or store them at colder temperatures such as 35-40 degrees F as well. If you are looking for control at this time, it would be best to spray the plants as you see the streaking damage beginning from the thrips feeding in the spring and summer months. You can use any general insecticide for this.

3. This caller has a sugar maple that was hit with hail 5 years ago and now has a great deal of damage to the trunk of the tree. They have sprayed the trunk with a sealant and used a wrap. Will the tree survive or should it be removed now?

A: At this point, I would observe the tree to watch for signs of death occurring through the tree. The damage that is there cannot be fixed now that it has occurred. If you don’t like the look of the damage you can remove and replace the tree or you can wait until it starts to dieback. It is hard to say how long the tree will live now that the damage has occurred.

2012-05-25 12.04.38

Bare lawn in need of overseeding.

4. A caller wants to reseed. What seed should he use?

A: For a new seeding, use a turf-type tall fescue or a Kentucky bluegrass. Use either 100% of either of these types or use a 50% mix of the two. For more information, see this article from the UNL Turfgrass Department on Choosing Grass Seed.

5. A caller has a section in fairly high shade that died out last year. Why and can it be reseeded?

A: In locations of very high shade turf doesn’t always do well. The caller said this had been growing there for 25 years so it could have been a fluke that the lawn died out last year. You can reseed now with regular turf or you can use a shady groundcover such as a carex species.

6. When is the time to transplant coreopsis to a location with more sun?

A: Now would be a great time. Mid April through mid-late May is a great time to transplant perennials.

7. This caller has some large pin oaks that need to be pruned to make it easier to mow underneath the tree. Is it too late now to do that?

A: Yes, it would be better to wait until late fall to prune the oaks now. Oak trees are susceptible to oak wilt which is spread by a beetle in the summer months. It is best to avoid pruning them at this time of the year to reduce the incidence of disease.

8. What kind of tree would be a good choice for shade production in a backyard?

A: Any of the oak species, shagbark hickory, sycamore, Linden, Kentucky coffeetree, Black locust, thornless honeylocust, hackberry, and many others.

Curly Dock, Steve Dewey, Utah State Univ, Bugwood

Photo of Curly Dock from Steve Dewey, Utah State University, Bugwood.org

9. A caller wants to know what to do for management of curly dock?

A: 2,4-D or Trimec can be used this time of year or use a mixture of 2,4-D and Roundup.

10. What do you do for thistles growing throughout a yard?

A: 2,4-D or Trimec, but these products are best used in the late fall or before flowering. Thistles are a biennial so if you can dig up the plants as a rosette in the first year of growth they will die.

11. This caller has cherry trees that are suckering. Can one of the suckers be dug up now to start another plant?

A: Yes, it can be done now, but fall would be a better time of the year for this. If it needs to be done, it can be done now. However, depending on the type of sucker growth, the new plants may not be the same as the original plant or they may have weak growth.

12. An email from a listener asked what is wrong with his pin oak that has leaves that are curled up like they were hit with a spray? He wondered if they were too close to the windbreak that is 20 feet away? Is there a certain distance you want to stay away from your windbreak when planting other trees?

A: You do need to give your trees space to grow, but pin oaks are often planted as a third, interior row to a windbreak. The spacing between rows would be 15-20 feet, so the proximity to the windbreak would not be a problem in this instance. Most of the time if a tree is lightly hit with spray drift from a pesticide, it will not show in the tree every year unless it is hit every year. In this case, I would ask for a picture or sample to help with further diagnosis.

13. When is the best time to transplant peonies? Why isn’t the rhubarb up yet?

A: Fall is the best time to transplant peonies. If necessary for construction or moving purposes, it can be done yet this spring. Plant them at the same depth at their new location. As for the rhubarb, give it a few more weeks to see if it comes up before giving up on it. If it is in a location that is more exposed to cold winds the soil may have not warmed up enough yet this spring.

14. This caller wants to know what type of fertilizer to use in a garden?

A: A low grade, balanced fertilizer is best for a garden, like a 10-10-10 or 12-12-12 with slow release fertilizer is best.

15. The final caller of the day wanted to know if now was the time to fertilize pecans?

A: Many of the trees in our environment have sufficient nutrients for growth and so fertilization on these pecan trees may not be necessary. If you are concerned with the growth of the tree, take a soil test to see where the fertility levels are. If it is growing fine, don’t fertilize it because our trees and other plants can be over-fertilized which can cause injury or even death.

Yard and Garden: April 7, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for April 7, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Hosts: Jonathan Larson, Extension Entomologist from Douglas-Sarpy Counties & Jody Green, Extension Entomologist from Lancaster County

1. The first question was to see if we could guess the caller’s favorite insect that was described as a moth with large, light green wings and feathery antennae?

A. This is a luna moth

2. A caller has moles in the yard and wants to know how to manage them?

A. A harpoon type of trap can be used, but should be prepped ahead of installation. This trap tends to work best if you stomp on a run to determine if it is an active run.  If it gets pushed back up, it is an active run. Stomp on this area a couple of more times and then set the trap to ensure the mole moves through the area. For more information on moles, click here for a publication from UNL on moles.

3. This caller wants to know how to get rid of creeping charlie in a lawn?

A. Triclopyr or a 2,4-D product can be used in the fall. For best control, use the product twice in the fall 2-3 weeks apart. September 30th and October 15th would be good dates for application. This is a tough weed to control, so it will take multiple years of multiple applications. A spring application of either of these products can be used as well to knock the weeds back for this year.

4. When can you transplant daylilies? Can they be planted into an area on the east side of the house with rock mulch?

A. Wait a couple of weeks until mid-late April to transplant them when the temperatures have warmed up more. Also, as long as the area is receiving at least 6 hours of sunlight daylilies will grow fine. This is a tough plant that will grow well in most conditions.

5. A caller has strawberries that had botrytis last year. When should they be sprayed to prevent the disease this year?

A. Apply from 5-10% bloom until flowers have finished blooming. For more information see the Midwest Small Fruit and Grape Spray Guide from Midwest Universities including UNL.

6. This caller has a pear tree that last year had orange spots on the leaves later in the season. What is this and how can it be controlled?

A. This is due to a rust disease, Cedar-Hawthorn Rust. It is more common in years following a wet spring. The timing for management is in the spring, May and June. See this NebGuide on Cedar-apple rust and related rusts of apples and ornamentals.

7. A caller has started corn, watermelons, and cantaloupe indoors from seed. The seedlings are getting quite large. Can they be transplanted outdoors now?

A. Unfortunately it is still too cold to plant these crops outdoors. These are warm season crops that should not be planted until early May after the frost-free date. These crops could be direct seeded at that time or transplanted but they tend to not do well as a transplant.

8. A caller has 2-year-old rhubarb plants that have come up and have thin, limp stalks. What is wrong with the rhubarb?

A. This could be due to crown rot. Rhubarb is very sensitive to high moisture soils and will often develop a crown rot in these situations. Those plants that have limp stalks should be removed and you can replant in a new location where it has more well-drained soil.

Bagworm4

Bagworm

9. When and what should you spray for bagworms?

A. May-June is the time frame for treating bagworms. It is best to spray them when the new bags are 1/2-1 inches long. Longer than that and they won’t catch as much of the pesticide to die as well. For spray choices, any general insecticide will work, but using Bt would be the least damaging to other insects because Bt only affects insects in the Order of Lepidoptera which includes butterflies, moths, and skippers.

10. A caller has Asparagus that has a green moss-like structure growing on top of the ground around it. What is it and what can they do for it?

A. A picture would be helpful in identifying this pest. If it is actually a moss, they may look into the water in the area because it is likely that it is too wet. If it is a weed, pull or hoe the weed and then add a layer of mulch to prevent further weeds from coming in.

11. This caller wanted to know what to do to grow bigger onions and if they should put Epsom salt on their tomatoes to help them grow more?

A. These onions are growing 3 inches apart, they should be spaced out more for larger sized onions. Place plants or sets 1-6″ apart in the rows, and 12-24″ between rows. For bulb production, plant onions in early spring. The number of leaves that form prior to bulbing determine the ultimate onion size. Since bulbing in each cultivar is triggered by a specific daylength, early planting is the most effective method of increasing bulb size, by allowing more time for leaves to form. If the onions do not grow well before bulb induction, the final bulb size may be smaller than desired. Avoid sets more than ¾ inch in diameter because they are likely to produce seed stalks.

As for the Epsom salt on tomatoes, no you should not apply this to your soil when you plant tomatoes. Our soils have a sufficient amount of magnesium and sulfate, which are the 2 ingredients in Epsom salt, so there is no need to apply more. If you need fertilizer, use a general fertilizer from the nursery or garden center.

12. A caller has a Japanese maple that was injured last May when the leaves curled up and fell off. The leaves never regrew through the summer last year. Will it come out of it?

 A: If it happened that early in the year last year and didn’t put on new leaves, it may be dead. Give it time this spring to green up. You can check if the tree is still alive by scraping the bark on a branch, if there is green underneath it is still alive, if there is brown it is dead.

13. What can you do to manage windmill grass?

A: Windmill grass is a perennial weed. You can use roundup and overseed or use a product containing mesotrione or Tenacity that will not harm your turf. Use the Tenacity in the late spring.

14. This caller wanted to know what to use for a pre-emergent herbicide in a strawberry patch?

A: Preen that is labeled for use in a vegetable garden would be allowed in a strawberry patch. The best control for weeds in strawberries would be to use mulch.

15. Can you use plants to repel insects?

A: Some plants may deter a few insects for a short time, but no, the plants are not concentrated enough to work against the insect pests.

16. A caller has an arborvitae that turned brown on the North side last fall. Will it be ok?

A: This could be due to bagworms or due to environmental stress. Arborvitae trees don’t like the sudden cool down in the fall and it can cause part or all of the plant to die quickly. Unfortunately, if the tree has turned brown all the way back into the trunk, the tree will not regrow on that section. Removal and replacement may be a better option for this plant.

17. This caller wanted to know when they can reseed their lawn and with what?

A: Mid to late April is the best time to reseed a lawn in Southeast Nebraska. Reseed with 100% Turf-type tall fescue or 100% Kentucky bluegrass or a 50% mix of each.

Squash bug-NH-pic monkey

18. A caller asked what to do about squash bugs in their vegetable garden?

A: Fall sanitation and cleaning up the garden will help a lot to reduce the eggs in the soil around your garden. When they do start coming out in the summer, you can use sevin, eight, or bifenthrin to control them. You will have to spray every 10-14 days through the growing season. Watch the Pre-Harvest Interval to know when you can harvest after spraying a chemical on your plants. You can also smash or remove the eggs you see which are tiny, football-shaped bronze colored eggs on the underside of the leaves typically found in the crotch of the leaf veins.

Yard and Garden: March 31, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for March 31, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Natalia Bjorklund, Nebraska Extension Educator in Dodge County

1. The first question was when can we begin applying crabgrass preventer and fertilizer to our lawns this spring?

A. These are both best applied in late April to early May. Crabgrass will not germinate until the soil temperatures are consistently at 55-60 degrees Fahrenheit.

2. A caller wanted to know if he should mulch his asparagus and if he can use ash wood mulch around his asparagus?

A. Yes, mulch is one of the best ways to manage weeds in an asparagus patch. Ash wood chips would be fine. You do want to avoid Walnut wood chips because walnuts produce juglone which is a chemical produced by the tree to act as a weed control for nearby plants. This helps walnut trees with competition in the wild.

3. This caller has a goldenrod that has grown too large and messy for the area where it is planted. How can it be killed and what Goldenrod would be a better choice for a less messy plant?

A. 2,4-D or simple hand removal should kill the plant. When purchasing a Goldenrod plant in the future, any of the varieties would be better than the straight species. Fireworks is a nice, open goldenrod. Wichita Mountains and Baby Blue would be good choices as well.

4. Is it too early to transplant hostas? When should you cut back warm season grasses?

A. Wait a couple of weeks to transplant the hostas until the soil has warmed up a little more. You can cut back the ornamental grasses anytime now. It is better to get the old growth cut off before growth resumes so you don’t cut off the new growth. For ease of cleanup with the ornamental grasses, wrap string or twine around the plant before cutting off the old materials so it stays together when taking to the compost pile.

5. A caller wanted to know how and when to prune roses?

A. Wait until a little later into April to start pruning them. It depends on the type of rose to know how to prune them. This sounds like a climbing rose which can be pruned back about 1/2 to reduce the size. Wait until they start greening up to know which areas of the canes have died back, the dieback should be removed as well. If the canes are long and lean over mowing areas or other things, they can be tied up to a trellis.

6. This caller wanted to know how to get rid of cockleburs?

A. While talking with the caller, it came up that the plant had very small yellow flowers on it and there were spines over the plant except right at the soil surface. This plant is in fact buffalobur, not cocklebur. These are easily pulled up if you pull where there are no spines. A 2,4-D product could also be used if there was a large amount of them in the lawn.

buffalobur, Howard F Schwartz, Colorado State Univ, Bugwood

Buffalobur plant from Howard F. Schwartz, Colorado State University, Bugwood.org

7. A caller wanted to know if they should water in their crabgrass control?

A. The label will explain to you how a product should be applied for best efficacy. Always read and follow the label instructions to apply correctly. For many of the crabgrass preventers, they would need to be watered in, but again, check the label to be sure.

8. When should asparagus be fertilized?

A. Apply a general fertilizer or a composted manure to the bed after the last harvest or sometime in the fall.

9. This caller has mulberries growing in the windbreak. After they are cut down, what kind of stump treatment should be done to keep them from regrowing?

A. 2,4-D concentrate should be used as a stump treatment. This will take multiple applications and will be more effective if done in the fall. Each time the 2,4-D is reapplied it should be applied into newly drilled holes or to a freshly cut area of the stump.

10. A caller has cedars growing in their landscape. Under the cedars there is bare ground. What can they plant in that area to avoid weeds coming in?

A. The cedars are going to keep that area quite dark and the cedars will take the majority of the water in the soil so mulch would be a good alternative. If plants are desired, use a shade tolerant groundcover such as wintercreeper or vinca vine or perennial plants such as bleeding hearts, hostas, coral bells, jacob’s ladder, and others.

11. This caller has tiny cedar trees coming up throughout the lawn. How can they be controlled?

A. Cut them off at ground level. If a cedar is cut below any lateral growth it will not regrow. Mowing over them wouldn’t be low enough.

3-step pruning cut

Proper pruning cut, University of Missouri Extension

12. When is the best time to prune a maple tree that had a branch break in a storm?

A. As soon as the storm has passed and it is safe to do so, you should remove a branch that broke in the storm. If the damage occurred in a winter storm, let the ice and snow melt off first. Then, hire a certified arborist to come out and make a good pruning cut so that the tree can seal off the wound quickly and fully.

13. A caller has a hibiscus tree that is turning yellow and many of those yellow leaves are falling off the tree. It was moved indoors during the winter months in an area of the house with low sunlight. What is wrong with it and will it survive?

A. Hibiscus plants would need more sunlight than what it has received through the winter. It should be fine once it gets more sunlight. As the days get warmer, you can move it outdoors for more intense sunlight. It should be fine once it gets moved to better growing conditions.

14. This caller has a weeping willow tree that they would like to prune up a little. When can they prune it?

A. The weeping branches shouldn’t be pruned up too much or they could lose their weeping habit. Willows tend to have a heavy sap flow in the spring if they are pruned then, so it would be best to wait until later fall to prune a willow.

15. This caller has grasses that are coming up among the gravel paths around his daylily patch. What can he use to prevent those plants from coming up?

A. Preen is a great way to stop the germination of annual weeds, such as many of our weedy grass species. If they come up before the preen gets put down or if they grow as a perennial weed, you can use a post-emergent herbicide. If it is a grass that is growing out of place among daylilies, you can use Grass-B-Gon or a similar product to kill grasses.

henbit, steve dewey, Utah State Univ, Bugwood

Photo of henbit is from Steve Dewey, Utah State University, Bugwood.org

16. What can be done to manage henbit?

A. At this time of the year, there is nothing very effective at controlling henbit. Henbit is a winter annual plant, meaning that it germinates in the fall and flowers and produces seed in the spring. It dies with the summer heat. As we are now seeing the purple flowers from henbit, there is no need to control what you are seeing. The seed is already present in the lawn for next year and what you would be spraying will die soon. You can hand pull it now and spray with a 2,4-D product late in the fall.

17. This caller has moon flowers that had a lot of hornworms on them last summer. What can be done this year to reduce the number of hornworms?

A. Just because there were hornworms there last year doesn’t necessarily mean you will have a lot this year. Hornworms are sporadic pests. They are easily controlled by hand removal. You can also use sevin or eight or any other general insecticide. Use Bt to protect other pollinators as Bt is only harmful to insects in the order Lepidoptera which includes butterflies and moths.

18. What do you do for bindweed in a vegetable garden?

A. If you haven’t planted yet this spring, you can roundup the plants before you prepare the soil for the summer vegetables. The plants will probably still be a problem later in the year as this is a difficult pest to control. When it comes back in the summer, you can carefully use roundup through the growing season. You can paint the glyphosate product onto the leaves of the bindweed avoiding spraying the desired plants.

Yard and Garden: March 24, 2017

Yard & Garden for blog, 2017

This is the Q&A for the Yard and Garden show for March 24, 2017. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through July 28, 2017. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Cole Thompson, Assistant Professor of Integrated Turfgrass Management at UNL

1. The first question of the year was a caller who had 2 peach trees that were three years old when they died last year. He cut the trees off and now there is suckers coming up from the ground where those trees were. Will these trees grow and produce peaches?

A. These trees will grow and will most likely produce fruit. However, they will not be a strong growth and the peaches produced may not be the variety that he originally planted. Many of our fruit trees are grafted to a hardier rootstock. If they die back or produce suckers, that growth will be the type of tree that the roots are not the type that the scion, or top part of the graft union, was. Also, because it is from a sucker, it is not going to grow as strong and upright as the main tree. He can try to keep them going but it would be best to plant new trees as well, if he has the space for both, he can keep both the suckers and new trees. If he only had room for a couple of trees, I would suggest starting the trees over from new trees.

2015-06-25 10.19.56

*Reference to commercial products or trade names is made with the understanding that no discrimination is intended of those not mentioned and no endorsement by University of Nebraska–Lincoln Extension is implied for those mentioned.

2. This caller wanted to know what the difference is between Roundup and Roundup 365?

A. Roundup 365 contains a chemical called imazapic which gives the traditional glyphosate product more of a soil residual. The Roundup 365 is labeled only for use on and around hardscape areas such as patios, gravel paths, and driveways. The label claims that it lasts in the soil for up to 12 months, so it should not be used around trees, shrubs, or areas you plan to reseed. Regular Roundup can be used in an area around plants and where you plan to seed after the recommended wait time. You would need to be much more careful with the Roundup 365 because of the soil residual around other plants.

3. A caller has pussy willow branches that were brought indoors and placed in water to begin rooting. They have now developed roots. Can they be planted outdoors now?

A. Yes, as long as the roots have begun to form and the ground can be worked, it would be fine to plant them outdoors now.

4. When is the best time to reseed a Fescue lawn in Southeast Nebraska?

A. Fall is the best time to reseed a lawn, but it can also be done fairly effectively in the spring. It is harder in the spring due to the weeds that compete with the grass seedlings. If you plan to reseed in the spring, it is best to wait until late April to early May for that. If you seed earlier in April, increase the seeding rate to compensate for the loss due to the colder temperatures. When you seed, you can apply tenacity or a mesotrione product to the seedbed to help with weeds. Tenacity is safe for use at seeding. It is also a good idea to seed with a starter fertilizer to help get your seed started strong.

5. This caller has a birch that was cut down last fall. The remaining stump is oozing a lot of liquid right now. How do they kill the birch entirely to stop the liquid from oozing out of the stump.

A. Birch trees are one of the species of trees that tend to “Bleed” heavily in the spring if they are pruned. They have a high sap flow in the spring which will lead to the oozing of large amounts of sap through any open wounds. On a normal pruning cut to a tree with high sap flow, it is not harmful to the tree. This tree still has living roots and the wound from cutting it off is exposed so the sap still will flow through. This tree either needs to be treated with chemicals to kill it or the stump needs to be ground out to stop this sap flow and to be able to plant new plants in the area. You can drill new holes into the tree and apply 2,4-D to those holes to start to kill the tree. With chemicals, it will take a few years to fully kill the stump.

6. Can raspberries be transplanted now?

A. Yes, raspberries should be planted as early as the ground can be worked in the spring, so now would be fine. It is best if the soil was prepared last year by spraying all the weeds and incorporating organic matter. This will help to ensure you have a raspberry planting to last many years.

2016-11-22 16.59.14.jpg

7. A caller planted grass last fall and held the seed to the seedbed with a biodegradable plastic barrier designed for seeding turf. However, now the plastic is not breaking down and it is getting stuck in the lawnmower. Is there anything they can do to break it down quicker? It will disturb the lawn too much to try to pull it out now.

A. Pulling it out without disturbing the lawn would be the quickest, but if that is not safe to do without tearing up the lawn, that isn’t the best option. Try to water it down or hope for rain, the moisture may help to break it down faster than it sitting dry. This winter was quite dry which may have delayed the breaking down process.

8. This caller had a giant tree fall in his yard. He has removed most of the tree but about 5 feet of the trunk is still standing in the yard. What can he do with the stump?

A. It would be best to cut that trunk off at the ground level and grind the stump out so that you can replant either with turf or with a new tree. If you don’t want to grind it out now or replant, you can cut it down to the ground level and place soil over it to allow it to naturally break down under the soil.

9. A caller has been growing watermelons but they tend to wither and die early in the year. What is wrong and how can he improve his crop?

A. It sounds like this caller has squash vine borers that get into his vines in the summer months. Squash vine borer is a type of moth larvae that gets into the stem of the vines and blocks the movement of water and nutrients through the plant. They are very common in melons, squash, cucumbers, and pumpkins. To avoid the damage from this insect, use a spray or dust formulation of sevin or eight on the base of the plant regularly through the growing season starting in June. You can also use aluminum foil or a toilet paper tube around the base of the plant to act as a barrier between the plant and the female squash vine borer adult who is trying to lay her eggs on the plant.

10. This caller has 25 bur oak trees that were planted 4 feet apart with the idea that some would die to space them out further. Most did not die and are still planted too closely. Will they grow that close together or should some be removed?

A. Bur oaks grow quite large, but in a forested area they will grow fairly close together. They will grow this closely together, however it will shade out many of the branches and it will cause conditions that are conducive to diseases when trees don’t have the space to have good airflow. It would be best to remove some of the trees so that the trees left behind are given 20 feet or more between them. They are only 10-12 feet tall at this time so they would still be fine to be spaded out and transplanted to another location if you can find someone to spade them and someone to plant them somewhere else.

11. Is it too early to plant onions? Is it time to cut back mums that are left from last fall?

A. Late March to early April is the best time to plant onions. Wait to cut back perennials from last fall. The dead plant material will protect them from freezing temperatures for another week or two. The plant material can be removed in the beginning to the middle of April.

12. This caller has a yard with high dog traffic. What type of grass would be best to stay growing through the dog traffic?

A. High traffic lawns will decline. Increasing the fertility will improve growth in this area. Also, if you could limit the traffic patterns from time to time through the lawn, this would help as well. Kentucky Bluegrass will recover better in high traffic areas.

13. A caller has a bean field area that he is trying to turn back to a grass area. What type of grass would do good in this area for an non-irrigated recreational area on an acreage?

A. Buffalograss would be great for an acreage area. Once it becomes established it wouldn’t have to be irrigated much or mowed at all. It is a very low maintenance grass species that is native and you can choose many different newer varieties. UNL has good seed selections. Because this was a bean field it might be over-tilled so a roller may be necessary to firm the soil up before planting. Buffalograss is a warm season grass so it should be seeded May 1st.

14. The final caller of the day has an established cedar windbreak. Some of the trees were removed recently and there is a bare area in the nearby trees where they were shaded out from the removed trees. This area is only 7 feet from the house. What can be planted in place of these trees to help block the bare area in the windbreak?

A. Because this is so close to the house, don’t go with anything too big. A larger shrub may be a good choice such as a viburnum, serviceberry, some dogwoods or even some lilacs may help fill in. Some slender growing trees may also work, but full size trees may grow into the house.