Yard and Garden: May 18, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for May 18, 2018. 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 August 3, 2018. 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

1.The first caller of the show has moss growing on the soil of an area where he is trying to plant blueberries and asparagus. Is the moss an indicator of acidic soils? He has used a pH meter and it all reads at 7.0 pH. How can he get the right soil conditions for these plants?

A. Moss does like living in acidic soils, but it will grow in most any location that is moist and typically shady. To know for sure how the soil pH is, it would be most accurate to get a soil test completed. Do a separate test for each section of this garden to know what is best for the blueberry area and what is best for the asparagus patch. Understand that blueberries do not grow well in Nebraska due to our weather and our basic soils. The soil would need to be amended around the blueberries every year to ensure the acidic soil they prefer.

2. A caller sprayed the lawn with a weed killer with crabgrass control 10 days ago. Can he go back in now to apply a fertilizer with a weed killer in it?

A. Without knowing the ingredients in the crabgrass control and weed killer it is hard to tell, but it if there is a weed killer in both the crabgrass control and the fertilizer it would not be advised to use both. It would be best to go in with just a fertilizer now and avoid the weed control for now. It is recommended to wait at least 2 weeks between applications of herbicides.

3. This caller divided and transplanted hostas last year, they are not growing as large as they had been before they were divided. Should anything be done to help them grow larger?

A. Give them time to get over the transplant shock and to build their roots back up. You can fertilize them as well to help them grow healthier. A general fertilizer for perennials would be helpful, a 10-10-10 fertilizer would benefit.

He also wanted to know if it is too late to transplant lilies this year?

A. It would still be fine to transplant lilies this year. Just make sure on very hot days you keep the plants watered.

4. A caller has a native grass patch that now has volunteer plants of Siberian elms and cottonwoods. How can these tree saplings be controlled without harming the grass?

A. If they are small and the population isn’t too high, mechanical removal can be beneficial. They shouldn’t regrow from a sapling. He could also use 2,4-D or a product containing triclopyr as a stump treatment for the saplings to ensure no regrowth occurs.

5. This caller has boxwoods that turned brown over the winter months. What can be done about this?

A. This is likely due to winterkill. Evergreen plants still transpire through the winter, if that transpiration exceeds the amount of moisture the plant takes in through the winter, desiccation can occur. Prune out the brown areas. As long as there are still green leaves on some of the branches, it should grow back.

6. A gentleman has a wildflower prairie area that is getting grasses and weeds coming in. What should be done at the end of the season with this wildflower garden to help reduce the weeds?

A. Mowing the weeds at the end of the season will help reduce the seedheads of weeds. You can also continue to add new plants to compete with the weeds, taller weeds will be most effective. For more information, visit this NebGuide on Wildflowers for the Home Landscape.

Wildflower Collage

Wildflower Photos from the Nebraska Statewide Arboretum at: arboretum.unl.edu/wildflower-week

7. A caller received a black chokeberry with a collection of plants. What is that plant? How should it be grown?

A. This is a nice, multi-stemmed large shrub that can grow up to 3-6 feet tall. It is a great plant for full sun and it produces berries, also called aronia berries, that can be made into jams or jellies but it is typically not eaten raw. Here is an article from the UNL Community Environment website with more information on Chokeberries

8. Is it ok to transplant a lilac shrub now?

A. It would be better to wait to do in the fall rather than right now. The lilac could be cut back to no more than 1/2 the size of the plant before moving, to make it more manageable. Do not cut it back to the ground for a few years to allow the plant to work more on building roots than on growing.

9. This caller has a double weeping cherry tree that has developed a frost crack over the majority of the trunk and now it is not leafing out. What can be done to save the tree?

A. The lack of leaf development may not be due to the frost crack. If a callus has begun to form on the frost crack, that is a good sign. Once the frost crack has developed, there is nothing to do to fix it. The lack of leaves could be due to cold damage from the winter, but not necessarily the frost crack. Give the tree some time to see if it is just late coming out of this long, hard winter. Don’t fertilize it now, it can do more damage to fertilize an already stressed plant. Scratch the bark off on some of the smaller twigs, if it is green underneath, the plant is still alive, if it is brown, the plant is probably not going to survive.

10. How long does it take for a pear to start producing fruit? This caller has one that was planted in 2015 and has not yet bloomed more than just a couple of blooms.

A. It can take pear trees up to 10 years to start flowering and producing fruit, but the can begin this as early as year 3.

11. A caller has a snowball bush he would like to transplant. When is the best time to move this plant and how is it done?

A. Fall would be the best time for this. To be most successful with this transplant, dig up as much of the rootball as you can and only cut the plant back up to 1/2 the size that it is now. When replanting, dig a hole just as deep and twice as wide as the rootball and backfill with the existing soil from the new location.

12. The last caller of the day has a sawtooth oak that was planted last year. As soon as it was planted it dropped all the leaves but regrow them through the summer last year. Now, the tips of the branches seem to be dying back and the tree is suckering at the base. He mulched the tree in and he waters slowly for 10-15 minutes every 2 weeks or less. What is wrong with the tree and will it survive?

A. The water amount is sufficient, but more often would be beneficial to the tree. Water a newly planted tree for about 15 minutes once a week. This tree is likely facing some problems with transplant shock, but should be coming out of that. The oaks are slower to come out of dormancy this year. Give the tree a couple more weeks then prune out the tips that have not developed leaves while the rest of the tree has.

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Yard and Garden: May 11, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for May 11, 2018. 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 August 3, 2018. 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, Professor of Viticulture, UNL

1.The first caller of the show has asparagus beetles. How can they be controlled?

A. Use a dust or spray formulation of Sevin to control the beetles. When using chemicals around vegetable or fruit crops, be sure to pay attention to the PHI listed on the chemical label. The PHI is the Pre-Harvest Interval which indicates how much time must pass between the application and harvest to avoid pesticide residues. You can also hand remove the insects, destroy them in a bucket of soapy water after removal. The asparagus beetle should be controlled because they will lay their eggs on the asparagus as it grows which can reduce the saleability. Also, their feeding can reduce the amount of ferns produced which can weaken the plant.

2. A caller has a Bing cherry tree that has been planted in the landscape for a few years and it is not growing and seems to be dying. What is wrong?

A. Sweet cherries, including Bing Cherries, do not grow well in Nebraska weather. For cherries in Nebraska, tart cherries will grow here and do best.

3. This caller has grapes that are not taking off that are in their second year of growth since planting. He has 2 varieties, but not sure which varieties they are. What should be done to get them growing better?

A. Grapes are self-pollinated, so only one variety is necessary. It would really depend on what varieties this caller is growing to know for sure what is wrong with them. They may not be the best choices of varieties for this area. For a listing of good varieties to choose from, visit the UNL Viticulture Program website. For good general care: the plants should be trellised and will be productive by the 3rd year. Water is very important for establishment in the first year. It would be beneficial to mound the soil around the base of the plant during the winter to work as insulation.

He also wanted to know if he could move strawberries into an old baby pool? Would this be enough space for the plants to grow?

A. They would be best grown in the ground, but could live in a baby pool as long as there are drainage holes in the bottom of the pool so the soil doesn’t get saturated.

blossom end rot zucchini

Blossom End Rot on Zucchini

4. How do you deal with blossom end rot in vegetable gardens?

A. Blossom end rot is due to uneven watering. It is technically a calcium deficiency, but the calcium is there it’s just not available to the plant due to the water issues. Even watering is going to be key, it is just hard to do in Nebraska when we face drought periods in between heavy rains. It is just best to water the plants 1 inch of water per week over the week to ensure even, adequate watering. Typically, when we see blossom end rot, we only see it for a couple of weeks early in the season, it is not usually a season-long condition.

5. A caller wants to control the dandelions in her lawn and also reseed. How can she do this safely?

A. We are really ending the window of opportunity for reseeding a lawn this year. It is difficult to get turf established when temperatures start to rise in May. Dandelions are best controlled in the fall with a broadleaf herbicide. At this point, the timing for both control of the dandelions and overseeding the lawn would be around the same time. However, you should not overseed the lawn and use herbicides at the same time or the herbicides could injure the turf seedlings. Tenacity, or a product containing Mesotrione can be used at seeding to control broadleaf weeds and not injure the grass seedlings. I would advise using this tactic in the fall or to overseed in late August to mid-September and allow the grass to grow enough to be mowed 3 times and then use a late fall application of a 2,4-D product to kill the dandelions. If there is time for a second application of the 2,4-D at least 2 weeks after the first application and into the early part of November, that would be most beneficial.

6. This caller has plum trees and elm trees growing in their peonies. What can be used to stop the regrowth of these weedy trees without harming the peonies?

A. The safest option would be to cut the trees off then paint glyphosate (Roundup) on the cut stumps shortly after pruning. Be careful to not get the glyphosate on the peonies to avoid damage to them. I would advise against using 2,4-D in this situation to avoid volatization of 2,4-D and causing problems to the peonies.

This caller also wanted to know if she can use Grass-B-Gon products in the peonies and iris’ to control grasses growing in the plants?

A. Yes, this is labeled for use in broadleaf plants to kill grasses.

7. A caller wants to know what she can use for weeds in the asparagus patch?

A. mulch is going to be the best option for any type of weeds in asparagus. Our herbicides are not labeled for use in this vegetable crop. After she is done harvesting the asparagus for the year, she can cut it back so all green growth is below ground and glyphosate (Roundup) can be used over the bed. This could be used in the fall after the season, followed by mulching the plants in to reduce new growth.

8. This caller has a disease on his pine trees. Is it too late to spray the trees to prevent the disease?

A. This is likely either needle blight or tip blight. The timing for spraying for needle blight is in mid May as the needles are emerging, with a second application in mid to late June, so it would be the correct time to spray for this disease. If the disease is the tip blight, the timing for spraying for that is in the third week of April, just before the needles emerge with a second application 7-14 days later. You would be past the prime window for this disease, but it would still be beneficial this early to treat for this disease as well to avoid too much spread of the disease. With the spring as cool as it has been this year, most things are pushed back a bit and fungicides would still be beneficial for these trees.

9. A caller asked why tordon could not be used for the weedy trees in the peonies that caller #6 asked about?

A. Tordon will kill the peonies as well. Tordon is a mobile chemical that can get from the roots of these trees and into the roots of the peonies, killing them as well. Also, Tordon is not labeled for use in a landscape setting, it is only labeled for roadsides and ditches.

10. This caller has 2 viburnums that are growing in her yard. One has leafed out fine but the other leafed out only part of the way and has now stopped emerging from winter dormancy. Will it be ok?

A. Don’t give up on the plants too soon this year. The spring has been quite cold and unusual for our plants. The general recommendation is to wait until June 1st before determining death in the plants. Because it started growing, it is likely that it will be fine. Make sure that the plant is getting plenty of water to help it pull through. If the plant begins to sucker from the base, this could be a sign that the top had cold damage.

11. A caller has 2 ornamental grasses that haven’t greened up yet. Will they survive or are they dead?

A. Just like with the viburnums, give the plants time to come out of their winter dormancy. Many of the ornamental grasses have not begun to green up this year yet. Wait until June 1st before deciding to destroy the plants that may just be slow to come out of dormancy this year.

12. This caller’s lawn is brown and pulls up with no roots attached. Could it be grubs?

A. If there are no roots attached to the grass, it is most likely due to grubs. Grubs can be managed with a grub control product applied to the grass in mid-June. For the grass that died, you can overseed the area in late August to early September.

13. A caller has a patch of rhubarb that is not growing much and is going to seed early. What can be done about that?

A. Rhubarb will start sending out seed-stalks in warmer weather. Some varieties, though, are more prone to send out seedheads early in the season. Cut off the seedheads as you see them start to form to push energy back into the roots and leaf production rather than into seed production for the plants.

This caller also wanted to know if you can root lilacs from a cut branch?

Lilacs are difficult to get to root. The best chances to get it to grow would be to take a piece from the base of the plants that has roots attached to it already. Divide the plant by taking a section off the side of the plant would be best.

14. What would be a good choice for an organic weed killer for dandelions?

A. If the population is manageable, hand removal would be the best organic choice. There are other products such as corn gluten meal and dried distillers grains which are used for pre-emergence weed control. According to the University of Minnesota, ‘It should be noted that any claimed herbicidal effects of Dried Distillers Grains have not been proven or verified as they have been for corn gluten meal’. For post-emergent organic weed control, vinegar can be used, but it is non-selective so it needs to be used as a spot spray. It is important to remember, that bees love dandelions and a small population can be tolerated and helpful for our pollinators.

15. The final caller of the day wants to know about mulching her garden. She uses straw but wheat comes with the straw mulch. What can she do?

A. Straw mulch can bring weed seeds with it, but it does make a great mulch for a vegetable garden. It would be best to shake the straw out over a tarp before applying it to the garden to pull most seeds out of it. Also, using older straw would help so that the seeds would have all germinated before use. Grass clippings make another great garden mulch. Just make sure that the grass was not treated with a pesticide before applying it to the garden. The pesticide label will tell you if or when those grass clippings can be used on a garden again this year. Grass clippings do break down quickly, so it is best to reapply this mulch often or the weeds will poke through.

Crabgrass

crabgrass, Joseph Berger, Bugwood

Crabgrass photo, courtesy of Joseph Berger, Bugwood.org

This time of the year is always full of activities to do outside. It is a great time to get outside in the comfortable weather. Lawncare is always at the top of our spring outdoor ‘to do’ list, and crabgrass is number one on the concerns.

Crabgrass Basics

Crabgrass is a summer annual grassy weed that takes advantage of thin areas in our lawns to become established. As a summer annual weed, crabgrass germinates in the spring and, if not controlled, new plants continue to germinate throughout the summer. Each plant grows for one summer, then dies with the first hard frost in the fall. New crabgrass that you see in your lawn each year is from seed that was set the previous year by the crabgrass growing before.

Crabgrass is a problem in our lawns. Each plant will compete with our desirable grass species. Once crabgrass gets into a lawn, it will compete with our grass for water, sunlight and growing space. Plants produce a large amount of seed that will germinate the following year, creating an ongoing problem on your lawn.

Prevention

Crabgrass is difficult to eradicate once it becomes established, so it is better to prevent this weed from becoming established in the first place. Crabgrass preemergent herbicides are used to inhibit the growth of young seedlings, destroying them before they can emerge from the soil. Which is why many people prefer to use a preemergent herbicide to control the crabgrass in their lawn.

Preemergent herbicides should be applied before crabgrass has started to germinate, which happens when soil temperature has reached 55-60 degrees F, measured at 4-inch soil depth, for at least four days. This is not based on a date range, because soil temperatures differ from year to year. It is based on the weather conditions for that year. We have reached that point now this year.

It is not beneficial to apply the preemergent too early in the year. Once applied products begin to degrade and breakdown. If your application is made too early, before crabgrass germination has started, you are wasting your product and monty because you will have a shortened period of control once crabgrass does start germination.

Plan on making two applications of preemergent to give season-long crabgrass control. Purchase enough product in spring for two applications; garden centers often run out of preemergent products by the end of spring so it could be hard to find later in summer. Each product has a slightly different length of residual action, so follow the product’s label directions on when the second application should be made.

Controlling Existing Plants

Post-emergent herbicides can be used to control crabgrass that has emerged in your lawn. Products containing Mesotrione, commonly found in the product called Tenacity, works as both a pre- and post- emergent herbicide on grasses and broadleaf weeds. It can also be used at seeding if you have a history of crabgrass problems and need to overseed.

The other commonly used post-emergent herbicide for controlling crabgrass would be products that contain Quinclorac, commonly found in the product called Drive.

If crabgrass does appear in your lawn, you can reduce future problems by keeping plants mowed short enough that they don’t produce seedheads. Then at least there won’t be additional seed in the soil to increase your problem next year.

Yard and Garden: April 27, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for April 27, 2018. 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 August 3, 2018. 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

1.The first caller of the show wants to plant hydrangea’s on the south side of a porch. Will they grow well in that location?

A. Most hydrangeas like part shade and wouldn’t grow as well in a location of south sun. However, ‘Limelight’ and ‘Little Lime’ would be good selections for full sun. The ‘Little Lime’ hydrangea will only grow up to 3 feet tall while ‘Limelight’ will grow up to 6-8 feet tall.

2. A walk-in listener has a 12 year old boxwood that is turning whitish-brown throughout most of the plant. What, if anything, can be done to save the plant?

A. This could be boxwood blight or winter desiccation. The fact that the boxwoods started to turn brown in the summer makes it less likely that it is winter desiccation. Also, the plant is brown and dead throughout the majority of the center of the plant, where winter desiccation typically only shows up on the top and outer sides where wind directly hits the plant. Either way, too much of the shrub has become dead branches so it should be removed. Boxwoods can be replanted into the area where the blight was a problem previously with no harm to the new plants.

3. A caller has Dwarf Alberta Spruce trees that have brown spots on them. Last summer he sprayed the plants with a copper fungicide, but should something else be done to them?

A. Dwarf Alberta spruce is prone to problems with spider mites in the summer months. If it is spider mites, when they start becoming active again, they can be killed with a strong spray of water. The bigger problem is that this is a very slow growing tree and it may never fill in again where the dead areas have appeared in the trees.

4. This caller has pecan trees that the top has died back on them over the winter. Can he prune it out and maintain the trees?

A. Give the trees time to leaf out this summer to know for sure where the dieback is found through the tree. With the cooler spring this year, many of our plants are slow to come out of their dormancy. Wait until the tree is fully out of dormancy before pruning it. After it has leafed out fully, cut the dead areas out, but cut back to a bud at the top of the tree so that you can use that bud to reestablish a new leader.

5. A caller has underground irrigation and planted a new lawn via seed and some via sod last fall. What type of watering schedule should he be on now?

A. Because this lawn was established last fall, you would not need to keep up the same schedule as last fall, the roots should be established now. Wait to start up the irrigation after spring rains begin. 1 inch of water per week would be the recommendation now, that is what established lawns require, so it would be the same for this lawn. Most often, we give our lawns 1 inch of water per week through 3 irrigation cycles of 1/3 inch each time. Make sure you check your irrigation rates when you first turn your system on for the year.

6. This caller has a 25-30 foot tall red oak in his yard. Every year for the past 2-3 years, the leaves come out cupped and small and stay that way through the entire growing season. What is wrong with his tree? He has other oaks in his yard that don’t look like this.

A. The cupping leaves sounds similar to herbicide drift. Typically, though, the trees will grow more leaves later in the season that are not cupped. If this was herbicide damage, it is likely that all the oaks in the yard would have this problem, but it still could be herbicide damage. It could also be from a small mite or other insect that is sucking the juices out of the leaves as they emerge. It would be best to bring a sample to the show or to Nicole to take to the lab for further testing. If it is herbicide damage, multiple years with damage to a tree can start to stress and kill a tree.

2018-04-20 12.52.00

Henbit blooming

7. A caller has a zoysiagrass lawn that is full of henbit for the first time this year. Is there anything to do for that now?

A. Henbit is blooming for the year now, which means it is already setting seed for more henbit to grow there next year. Henbit is a winter annual that germinates in the fall, goes dormant over the winter, then comes up in the spring and flowers and produces seed before it dies with the summer warmth. Because it is getting so late in the year and the seed is already there, there is no reason to treat for henbit now. It will die soon, once the temperatures warm up. next fall, treat with a 2,4-D product in October or November to kill it as it first germinates in the fall.

8. How do you control Creeping Charlie in the lawn?

A. Creeping Charlie is best controlled in the fall months with a 2,4-D product or a product containing Triclopyr. It is best to do 2 applications in the fall, one in the middle of September and another at the end of October. The caller was going to overseed, so it was advised to overseed this spring and then treat the Creeping Charlie in the fall for best control. It will take multiple years of treatments to fully reduce or eradicate Creeping Charlie, but spraying in the fall will start knocking it back.

9. This caller has Sod that was installed last November and now some cracks have shown up between the sections of the turf. What can be done to fix that?

A. Add some soil to those areas of bare ground and then reseed those areas. Cover the new seed with peat moss while it establishes to keep it moist.

10. A caller wants to know how to plant strawberries and what varieties are good choices?

A. Sarah Browning, Lancaster County Extension, has written a good article on Planting a Strawberry Bed

11. The last caller of the day wanted to know if they should till their garden before planting and when to prune her hydrangea shrub?

A. If the soil is loose and has a good level of nutrients, you wouldn’t have to till it first. It might be a good idea to till it first to loosen it up and to add nutrients back into the soil for better production.

As for the hydrangea, this is a late summer blooming hydrangea, so it can be pruned now and still produce flower blooms for August or September this year. It can be pruned back to the ground if it is overgrown. If it is not too overgrown, the largest canes can just be cut out of the plant, leaving the more productive, smaller canes in the plant to grow.

Yard and Garden: April 13, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for April 13, 2018. 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 August 3, 2018. 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: Kyle Broderick, Coordinator of the Plant & Pest Diagnostic Clinic at UNL

1.The first caller of the show wants to know when is the time to trim roses?

A. Anytime now would be good. When the show aired, snow was predicted for over the weekend, so it is advised to wait until the snow has melted before pruning the roses to avoid damage from cold weather.

This caller also has moles, how do they get rid of them in the yard?

A. Harpoon traps work best for moles. To help the trap work better, stomp down a run 2-3 times before placing the trap in the run. This shows that it is an active run and it will lead the mole to continue to pop the soil back up after you knock it down. For more information, visit the UNL Wildlife site and choose the NebGuide on Moles

2. How do you kill grass growing in peony plants

A. Fluazifop is the active ingredient found in Grass-B-Gon products. This will kill grasses and not harm ornamental plants. It can be sprayed right over peonies and iris’ and other ornamental plants. Be sure to not spray your turf or ornamental grasses with this product as it will kill any grass it contacts.

3. A woman has a substance on her artificial turf. Is it mold or moss?

A. It would be moss if it has a green color, but if it is more of a black color, it would be mold. Dry out the area to reduce the problem. You can also clean the artificial turf with a vinegar solution.

4. A caller has an apricot tree with blossoms that are starting to show color. Is there anything that can be applied to protect it from the frost, snow, and cold temperatures in the forecast for the weekend?

A. There are no sprays to protect the fruit tree from cold damage. Watering the tree prior to the cold weather can help protect it because trees use moisture to protect itself in cold weather. This is the reason that peaches and apricots have years of low production, they tend to bloom earlier than the frost free date which will cause cold temperatures to damage the developing flower buds.

This caller also wants to know if they should spray their trees for pests now or if they should apply preen in their gardens?

A. No on both of these questions. There is snow and rain in the forecast which will wash the pesticides off the trees. It is too early to use preen because it stops the germination of annual plants. Winter annual plants emerged last fall and summer annual plants won’t germinate until the soil temperatures have warmed up more. Applying preen too early in the season will cause it to break down sooner in the summer allowing later germinating summer annual plants to emerge once the preen is gone for the year. It is best to wait until soil temperatures have warmed up closer to when the seeds will germinate.

Ant mounds from YandG listener

Larger Yellow Ant Mounds

5. This walk-in listener has mounds that developed in their pasture area after they burned it this spring. What are the mounds from?

A. These mounds developed from ants. Upon closer inspection, Jim Kalisch from the UNL Entomology department, has determined the ants are Larger Yellow Ants. The mounds will persist as long as the land is not tilled. The ants favor building their nests in clumps of bunchgrass, as it provides stability and protection, and the ants tend root aphids on the bunchgrass roots underground. If the mounds are not desired, tilling the ground will reduce the mounds.

6. Can preen be used on asparagus before it emerges?

A. Yes, preen only stops the germination of annual seeds. Asparagus is a perennial plant coming back from the roots, so it will not be inhibited from growth if the preen is applied before it comes up. Make sure you are using the preen that is labeled for use in asparagus, not the general preen that is used in ornamental plantings.

7. A caller has grubs in his vegetable garden space. What should be done about that?

A. A few grubs in the garden won’t be problematic. Mostly, grubs are only damaging to potatoes and not our other vegetable plants. If the population is high enough and damage is occurring, the vegetable garden would need to be moved for a year to treat with chemicals that are not labeled for use in a vegetable garden. There are no products available to treat grubs that are labeled for use in vegetable gardens safely.

8. This caller is taking care of a planting of hostas for the first time. What does he need to do to clean up the space?

A. Hostas die back to the ground every year, so once the weather is a little warmer more regularly, these plants can be cut off at the ground level to remove all of the dead leaves and plant material from last year. Make sure to refresh the mulch to 2-3 inches deep with new organic mulch. If the plants are too big, they can be divided and replanted in other locations. Depending on the size of the plant it can be divided into 2, 3, or 4 parts to replant in other locations or to share with friends. To divide the plants, dig them up and use a spade to cut it into pieces that are then replanted.

9. A caller has white pine trees that were transplanted last year that are now turning brown on the ends of the branches. What is causing this?

A. This could be due to a combination of transplant shock and winter injury. Fall watering will help protect newly planted trees from winter injury. Water these trees well throughout the season and they should improve over time.

10. This caller has an angel wing begonia that is overwintered indoors each year. Can it be placed outside during the summer months?

A. Tropical-type plants, such as this begonia, will not take temperatures below 50 degrees F, but they can live through our summer months. Once the temperatures are consistently in the 50’s and warmer, the potted plant can be placed outside. To prevent breakage of the branches, it would be best to place the planter in a location that is protected from high winds. Next fall, before the temperatures move too cold at night, move the plant back indoors to keep it alive through the winter. Spray the plant with an insecticide before bringing indoors to keep insect pests outside instead of bringing them indoors with the plant.

11. A caller has scrub elm trees that have started growing up in the asparagus patch. What can be done to kill the elm trees?

A. Right after cutting the elm off, paint the stump with a straight 2,4-D product. Don’t use tordon or triclopyr products as these can get into the roots of the asparagus, killing it. Treat the stumps early in the season before temperatures reach 80 degrees F to avoid volatization of the product and causing possible harm to the asparagus.

12. This caller has gnats from houseplants in the office. How can they control them?

A. These are likely fungus gnats from the houseplants. If you know when the gnats first appeared and you can link that to the appearance of a new houseplant, remove that houseplant to remove the majority of the gnats. Houseplant insecticide sprays can also be used. Repotting the plants, removing the majority of the soil from the roots will also help.

13. The last caller of the day wants to know how to control grass in a well-established asparagus patch?

A. You can spray the bed with glyphosate (Roundup) before the asparagus has emerged and no green from asparagus is present, but the grass is green. It would also be best to apply mulch around the plants to reduce new weeds from emerging.

Plant a Tree for Arbor Day

Plant a Tree blog, 2018

One of my favorite holidays is coming up, Arbor Day. As a tree enthusiast, I appreciate any holiday that urges people to plant trees. Arbor Day is always celebrated on the last Friday of April in Nebraska, this year that is April 27th. This holiday is not the same throughout the United States, it is moved around for other states to be in the best planting time for the year.

Deciding what tree to plant is very important and sometimes difficult. Diversity is key when choosing your tree. The general rule is to plant no more than 10% of a tree species, no more than 20% of a tree genus, and no more than 30% of a tree family in a respective urban area. Look around at what types of trees you have and what types of trees your neighbors have before deciding on a new tree, try to avoid everyone planting the same few trees throughout the neighborhood. Look for some unique, underutilized trees such as gingko, Kentucky coffeetree, Ohio buckeye, hornbeam, paw paw, sweetgum, or tulip tree for deciduous trees that do well in southeast Nebraska.

The most important factor to keep in mind when planting trees is how to plant a tree correctly to ensure healthy growth. First of all, remove all of the burlap and any other materials from the root ball before planting. Also remove any tags, twine, or wire from the tree. Remember to remove all the grass and weeds that are within the area you will be planting the tree. Dig a hole that is 2-3 times wider and no deeper than the root ball and loosen up the sides of the hole. Plant the tree so that root flare is at the soil surface. Do not amend the soil that is in the hole, backfill with the existing soil. Make sure that the entire root ball is covered with soil to avoid drying out.

Keep newly planted trees well-watered. Always water newly planted trees, shrubs, or any other plant immediately after planting. Trees should be watered every 10-14 days throughout the growing season and even some during the winter on warmer days. Each watering should give the tree 1-2 inches of water. The best way to determine if a tree needs to be watered is to insert a soil probe or 12-inch-long screwdriver into the ground around the tree. If it goes in easily there is no need to water, if it is difficult at any point then water is necessary for the tree.

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Tree Damaged from Lawn mower blight

A mulch ring should be established and maintained around every tree. Mulch helps to keep the roots cool in the summer and regulated to a uniform temperature through the winter. Mulch will also help keep weeds down and reduce competition from those weeds for water and nutrients. Mulch also reduces damage to the trunk of trees from lawn mowers and trimmers. Finally, organic mulch is a way to hold moisture for use later by the tree. Mulch rings should be only 2-3 inches deep and in a circle around the tree at least 2-3 feet out. Organic mulches are a better choice than inorganic mulches. This mulch will need to be renewed every year to maintain an effective layer because it will break down over the growing season which will improve the soil.

Tree Planting, 2017 (3)Staking a tree is not a mandatory practice. If you do have to stake the tree due to high winds, make sure that the tree has plenty of movement to allow it to build stronger roots. Also be sure that the staking material is removed after the first year to avoid the tree being damaged by the staking materials.

Yard and Garden: April 6, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for April 6, 2018. 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 August 3, 2018. 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, Douglas/Sarpy County Extension Educator in Entomology and Jody Green, Lancaster County Extension Educator in Entomology

1.The first caller of the show has little blue flowers in her lawn. How can she get rid of them?

A. This is likely speedwell, it is a winter annual plant so it blooms very early in the spring then dies with warmer weather. At this point, since it is already blooming, just leave it as it will die soon and the seed is already set for next year. Spray it with a 2,4-D product late next fall after it has germinated or use a pre-emergent herbicide in the earlier fall before it germinates.

2. What is the correct mowing height?

A. 2.5-3.5 inches is the recommended mowing height for cool season turf in Nebraska. Too low will lead to more weed pressure and insect and disease issues because the turf cannot compete with these pests when it is too short. Make sure you mow enough to mow off only 1/3 of the turf blade each time you mow to avoid scalping the turf.

3. A caller asked if the treatments for Emerald Ash Borer (EAB) were killing the trees?

A. The most effective treatment methods for EAB are trunk injections, which can harm the tree. However, the tree can take about 10 treatments before stressing the tree to the point of death. If you are using Emamectin benzoate as the trunk injection chemical, the tree will only need to be treated every 2-3 years, giving it 20-30 years of injections before harm occurs. For the first few years of treatments, you may be able to use a soil drench rather than a trunk injection, again adding more time with your tree. A soil drench will work, but once the tree grows to 15-20 Diameter, the soil drench is not as effective. In the 20-30 years of treatments, you can get a very good start on a new tree nearby the ash tree to have a well-established tree growing in it’s place for when the ash tree needs to be removed.

Termites

Termites, Photo from the University of Nebraska Department of Entomology

4. Does wood mulch attract termites?

A. If the wood mulch is piled up so high to where the mulch is touching wood siding, it can be a pathway for the termites to enter the home. However, mulch is recommended to only be 2-3 inches deep and most concrete foundations will go higher than that. Also, if you have had termites in the past, you should be working with a pest control company for termite control and the chemicals will manage the termites from the mulch. You will not get termites from mulch, the mulch is cut up too small and termites will dry out in that condition, so that cannot happen.

5. This caller is replanting a windbreak. They have begun with an outside row of cedars and would like to know what to plant on the interior rows?

A. An interior row with multiple types of trees is best. Diversity will help your windbreak survive better if another disease or insect problem comes in to kill evergreen trees like pine wilt has. Good evergreen choices include blue spruce, black hills spruce, concolor fir, Douglas fir, ponderosa pine, white pine, and Norway spruce. You can even add in deciduous trees like oaks or maples to fill in as well.

6. A caller wants to know how to control poison hemlock on the edge of his field?

A. 2,4-D and Dicamba in a mix. This mixture is found in the product called Trimec as well as others. It is best to treat the poison hemlock while it is in the rosette stage, so early spring or fall. Do not allow cattle access to the dry matter after this has been sprayed.

7. This caller wants to know if fertilizer is needed to trees as they plant a new windbreak?

A. Fertilizer is not necessary for trees planted in Nebraska. Our soils typically have plenty of nutrients available for use by the trees. It wouldn’t hurt to add fertilizer at planting, but it isn’t necessary.

8. The final caller of the day wants to know how to plant a new asparagus patch?

A. Asparagus is a great plant for a home garden. Many people want to get plant starts from a neighbor to start their patch, but it is best to just purchase a new set of crowns. When planting asparagus crowns, dig a trench 8-12 inches deep and bury the crowns only under 2 inches of soil. As the plants poke up through the soil, add more soil until the soil is level. Avoid harvesting asparagus until the third season of growth to allow the crowns enough time for root production. For weed control, mulch is best, such as wood chips or grass clippings. Preen that is labeled for use around asparagus can be used in the spring to prevent annual weeds from germinating. In late May to early June, when finished harvesting asparagus for the year, you can break all the spears off below ground, leaving no green growth above ground, and spray glyphosate or Roundup over the bed to reduce weeds. After this, allow the plants to grow back up and produce ferns which will produce seed and help your patch grow. You can cut it back in the fall or in the spring before new growth begins.

Yard and Garden: March 30, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for March 30, 2018. 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 August 3, 2018. 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: Justin Evertson, Green Infrastructure Coordinator, Nebraska Forest Service

1.The first caller of the year has brown rot in her apricot and cherry trees. How can this be managed this spring?

A. Brown rot is a fungus that affects the fruit of stone fruit trees. Spraying with Captan or Chlorothalonil products or using an Orchard Fruit Tree Spray throughout the growing season will reduce the disease. Avoid spraying during bloom if using a combination spray that contains an insecticide to avoid damage to pollinating insects. For more information on spraying and timing, visit food.unl.edu/local-food-production and click on ‘Managing Pests in Home Fruit Plantings

2. A caller has been advised to use a type of fescue called ‘Water Saver Fescue’ because it is more drought tolerant. Would this be a good turf choice?

A. This variety is a turf-type tall fescue variety that is an RTF variety. The RTF is a new type of tall fescue that forms rhizomes, allowing it to fill in a yard rather than just form clumps like the traditional tall fescue. Turf-type tall fescues are preferred to other types of grasses because they do well in our environment and are more drought tolerant than other turf species, such as Kentucky Bluegrass. This wouldn’t be any more drought tolerant than any other turf-type tall fescue species, but it would be drought tolerant.

3. When should a person fertilize their lawn?

A. If using the maximum fertilizer applications for a year, we recommend fertilizing with the holidays: Arbor Day, Memorial Day, Labor Day, and Halloween. It is not necessary to do all of these fertilizer applications. If you leave the grass clippings on your lawn, that replaces one fertilizer application over the course of a growing season. If you only apply fertilizer one time per  year, the best time is at Halloween. If you would like to apply 2 applications per year, the other time would be to add an application on Arbor Day.

4. This caller wants to know what is best to use in a vegetable garden to keep the weeds down?

A. In a home vegetable garden, mulch is going to be best for weed control. There are a lot of mulch products that can be used in the garden to reduce weeds including: wood chips, grass clippings (that have not been treated with any pesticides), newspaper, leaves, and cardboard.

green-asparagus-pixabay5. A caller wants to plant a new asparagus bed. How should she go about planting and caring for her asparagus?

A. Asparagus is a great plant for a home garden. Many people want to get plant starts from a neighbor to start their patch, but it is best to just purchase a new set of crowns. When planting asparagus crowns, dig a trench 8-12 inches deep and bury the crowns only under 2 inches of soil. As the plants poke up through the soil, add more soil until the soil is level. Avoid harvesting asparagus until the third season of growth to allow the crowns enough time for root production. For weed control, mulch is best, the same mulches used on a vegetable garden work great for asparagus beds. Preen that is labeled for use around asparagus can be used in the spring to prevent annual weeds from germinating. In late May to early June, when finished harvesting asparagus for the year, you can break all the spears off below ground, leaving no green growth above ground, and spray glyphosate over the bed to reduce weeds.

6. This caller has Colorado Spruce trees with needles at the bottom of the tree that are turning brown. What is wrong with the tree and how can it be fixed?

A. This is likely due to needle cast disease. You can spray the tree for needle cast in May using a liquid copper fungicide. For more information, view this Nebraska Forest Service publication on Diseases of Evergreen Trees.

7. When is a good time to transplant Iris and Peonies?

A. The best time is in the fall, but it can be done now. They may not bloom this spring if you move them now, but will bloom again next year. Be sure to get the peony planted at the same depth it is now or it won’t bloom.

8. A caller has a vine growing on the trees they thought was poison oak. How can it be controlled?

A. It is likely that this is woodbine or Virginia creeper. It doesn’t all have to be killed off, it makes a great groundcover. Cut off the parts growing up the tree and leave the rest for a groundcover. If you need to manage it cut it off and treat with glyphosate or triclopyr or just hand pull.

9. The final caller of the day has recently read that trees can “communicate” to other trees if they are attacked by a pest to help the other tree prepare to defend themselves from the pest problem. Is there any research on this?

A. There is a theory that trees communicate. A German Forester is looking into this idea further. Here is the Article from the Smithsonian Magazine regarding this topic and the research on how trees communicate.

What to do in the Spring?

Spring Things Blog Post

Spring is here. That is wonderful for the weather and the desired plants and flowers, but it also means the insects and weeds are coming back. If you know what you are dealing with, management is achievable.  

Henbit

Henbit is one of those not so desirable weeds that shows up in our lawns in the spring. We don’t really notice it until it begins to bloom and at that point, it is too late for control. Henbit is the early spring weed that blooms purple along the edges of our sidewalks and driveways.

henbit, steve dewey, Utah State Univ, Bugwood

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

Henbit is a winter annual. This means that henbit only lives for one growing season, but it’s development is different from something like crabgrass which is a summer annual. A winter annual is a plant that germinates in the fall and grows a bit before basically becoming dormant for the winter months. Very early in the spring, henbit will start to grow again, produce flowers and seed for the next year then it will die when the temperatures warm up. This is different from a summer annual which germinates in the spring and goes through its lifecycle through the summer months and dies with our fall frosts.

The problem with henbit is that by the time we see it, or rather see the purple flowers, it is too late to treat for the year. Once the flowers begin to show up, it is already producing seed for next year, so killing blooming henbit is unnecessary because it will die naturally and the chemicals won’t reduce production for next year. However, pulling the plant would be a fine management practice after blooming has begun. It can be sprayed with a 2,4-D product very early in the spring once it has greened up but before it blooms. If you know where it is you can spray it before it blooms. Otherwise, wait until this fall to spray those areas with a pre-emergent herbicide before it germinates in the fall.

Lawncare

This is the time of the year when we want to start seeing color in our lawns. We begin to think we need to fertilize, overseed, and use crabgrass control. Don’t get ahead of the weather with these things. It is still fairly early for overseeding, it can be done in April, but anytime by the end of April to the early part of May is still fine for overseeding. Overseeding too early could cause the seed to germinate in warmer weather. If that warm weather is followed by freezing temperatures, it could damage the newly emerged grass. Fertilization should not be applied until mid to late April when temperatures warm up more consistently.

Crabgrass preventer should not be applied too early in the year either or it will break down before the crabgrass begins to emerge. Crabgrass preventer should be applied when the soils are consistently at 55-60 degrees Fahrenheit. A split application, applying more 6-8 weeks after the first application will ensure crabgrass control through the season.

Asparagus

green-asparagus-pixabayAsparagus is a great vegetable that many people enjoy growing and eating. Now is the time to clean up your asparagus beds if you haven’t done so already. It is a good practice to allow asparagus fronds to stand through the winter to help trap snow during the winter months, providing moisture for the crown of the plant as the snow melts.

If you are planting a new asparagus bed, dig a trench 6-8 inches deep and plant the crowns in that, only covering with a couple of inches of soil. As the plants grow up through the soil, continue to add a couple of inches of soil at a time until the soil in the trench is level with the surrounding soil. Wait for 3 years before you begin harvesting to allow the roots to get fully established.

Salt is not a recommended weed control for asparagus. Asparagus is a salt tolerant plant, but it doesn’t thrive in salty soil environments. Also, the salt in the soil can begin to break down the surrounding soil, leaving you with bad soil for the asparagus and other plants growing nearby. For weed control, it is best to use mulch throughout the season.

Mulch

2012-04-04 13.24.59

When I think about spring, I always think about planting. It is fun, stress relieving, and rewarding for me to get my hands dirty and plant some new plants or change what I have in my garden. One thing to always remember when planting a garden or cleaning up an existing one is the mulch.

Mulch is a great benefit to our plants. Mulch can help work as insulation for our plants through the winter months, protect them from lawnmower blight, hold moisture near the plants, and reduce weed competition.

In the winter months, mulch is helpful to keep our plants insulated from freezing temperatures. However, mulch does not necessarily keep the roots of the plants warm, it keeps the temperatures from constantly freezing and thawing. In the winter months, freezing and thawing of the soil can push the plant out of the soil in a condition called frost heaving. This can expose the crown to winter temperatures and possibly kill the plant. We often add extra mulch during the winter months to help protect our plants more. The plants then are adjusted to growing in the conditions under the extra mulch, which is why it is important to wait to uncover them for the spring. If the plants start to green up under the mulch or pop through the mulch you can pull the mulch back away from the plants, leaving it nearby to cover the plants back up if freezing temperatures are predicted again. It is best to wait until early May to fully uncover those plants, once the threat of frost has passed for the year.

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Tree damage from Lawn Mower Blight

Mulch also helps protect our plants from a condition we refer to as ‘lawnmower blight’. Lawnmower blight often occurs to our trees and shrubs growing right in the turf with no mulch around them. It is when the mower or weed trimmer gets too close to plants damaging the trunk or branches of the shrub. This damage disrupts the flow of water and nutrients through the tree, but it usually does not kill the plant. Having the mulch ring will keep the lawn equipment back away from the tree.

 

Mulch is also great for our plants during the spring and summer months to help keep moisture near the plant and reduce competition from other plants around the tree or other desired plants. Wood chips will hold moisture that will eventually be released back out to the plants for extended water availability. The layer of mulch will also help reduce competition for water, nutrients, and space from other plants growing nearby. Turf is included as a competition for our landscape plants. It is best for the overall health of our desired plants to keep the competition limited around the roots.

Mulch needs to be applied correctly to help the plants, if applied incorrectly it can damage them. A layer of mulch 2-3 inches deep is the recommendation. Too deep and you can start to starve the roots of oxygen and the roots may begin to grow in the mulch out of the soil. If the mulch is applied to shallow, weeds will come up through it. Avoid mulch volcanoes which can cause a great deal of damage to the plant. Coarse textured mulches are better for plants than fine textured mulches which can become compacted, reduce oxygen to the plants, and allow more weeds to penetrate.

Organic mulches are preferred over inorganic mulches. Organic mulches would include wood chips, straw, leaves, and untreated grass clippings. Inorganic mulches such as rock or crushed rubber would not give the benefits to plants that organic mulches would. Inorganic mulches do not hold onto water and they make the plants and the roots much hotter in the summer and reflect that heat onto the plant causing more drought and heat stress to the plants. Inorganic mulches would be best used in xeric landscapes and rock gardens.