Yard & Garden: May 8, 2020

This is the Q&A for the Yard and Garden show for May 8, 2020. 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 31, 2020. 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: No guest host due to COVID-19 and social distancing

1. The first caller of the show has shrubs that bloomed this spring, when can they be pruned?

A. Any shrub that blooms in the spring should be pruned within about 3 weeks following the spring bloom period. This would include plants like lilac, forsythia, and the spring blooming spireas.

2. A caller heard me discussing the need to cover tender annuals for the next few nights with the cold temperatures predicted. Do those need to be uncovered during the day or can the cover just stay on for the next few days? Does she need to cover her wisteria or strawberries that are just beginning to bloom?

A. The plants that should be covered are annuals and tender perennials, this includes the warm season crops that have already been planted in your garden this year. You can cover them with a sheet, a row cover, or a bucket. They should only be covered at night. In the morning, when the temperatures warm up above 40 degrees, the coverings should be removed to allow the plants to receive sunlight. Perennials, including wisteria, should be fine. Strawberries that have blossoms set would push new flowers and fruit later but if you don’t want to lose this first crop, you may put a row cover or sheet over the plants to protect the developing fruits.

3. This caller has a flowering tree that is suckering in the lawn. How can they control the suckers without harming the tree?

A. If these are growing in the yard, they can just be mowed over and will eventually die but not harm the tree. You can also cut the suckers off individually, if desired. Don’t treat these with any herbicides like roundup because it can go into the main tree and kill that as well. While some products, such as Sucker Stop are available, these will only slow sucker growth; not stop it. Some trees and shrubs are more prone to suckering. For example, crabapples, purple leafed plums and lilac.

4. A caller has 3 acres of bare area to manage. What is the best or cheapest options for him regarding grass or some other type of covering?

A. Native grass or pollinator or wildlife mixes would be a great option for this type of location. You can purchase seed at many locations including Anderson Seed from Odell or Stock Seed Farms from Murdock.

5. This caller has black spots on her grass that have recently showed up. She wasn’t sure the type of grass but most likely it was Kentucky bluegrass.

A. It is hard to tell for sure what the problem is from the description given. I asked for a photo to be emailed to know for sure.

cedar-apple rust gall
Cedar-apple rust gall on Cedar Tree

6. A caller has cedars that have developed odd orange structures on the branches. What is that and how can it be controlled?

A. These are the galls of cedar-apple rust. This disease needs 2 hosts to complete its lifecycle. The galls are hard, gray/brown structures on the cedar trees over the winter. In the spring, when it rains, these galls open up to allow the spores to move to the apple trees. When the galls open up they are orange structures that resemble an octopus due to all the telial horns around the gall. The disease causes no problems to the cedar trees, but will cause lesions on the leaves and fruits of apple trees. If you have a susceptible apple tree, now is the time to spray with a fungicide to prevent the disease from affecting your tree. For more information, view this NebGuide.

7. This caller has asparagus growing. This is the 4th or 5th year of growth. He has fertilized often but not this spring. He did use a weed and feed on the asparagus, but asparagus wasn’t listed on the label. Why is his asparagus growing so spindly?

A. As we harvest, eventually the spears will start to get spindly which means that is the time to quit harvesting for the year. However, the weed and feed product may have some negative consequences on this plant. He didn’t know what exactly the product was that he used but he said it didn’t have asparagus listed on the label. In this case, the product should NOT be used on the asparagus. Make sure to always read and follow the label on pesticides and only use it on plants listed on the label.

8. A caller has planted potatoes a couple of different times this year, but they continue to not sprout. What would be the problem?

A. The weather has been fairly cool, and especially cold overnight. The plants are just waiting for more desirable weather before growing. Give them a little more time and they should grow as long as a disease doesn’t set in or they rot in the ground.

9. If volunteer redbuds have come up throughout a landscape, can they still be moved to a more desired location this year or is it too late?

A. Yes, they can still be moved now. As long as they are moved prior to the hot, dry environment of late June through July and August, they should be fine.

10. What is the best way to manage weeds around asparagus?

A. Mulch is the best option to keep weeds down around asparagus. You can use the preen that has asparagus listed on the label to control annual weeds. Otherwise hand-pulling will help keep them down as well. At the last harvest of the season cut down all the spears, so there’s no foliage or anything above the ground. Rake the soil over the top of the spears. Then spray the plants with glyphosate (RoundUp). Glyphosate becomes bound by the soil particles when it hits them, so will not damage the crowns below ground. This will control annuals and tough perennial weeds. The spears will then re-emerge from the soil and not be damaged by the glyphosate at all. Apply some mulch to help with the weed control, then Preen.

11. This caller gets little brown spots on the leaves of her cucumber plants every year. This often will kill her plants over time. Is there anything she can do to control this so her plants will survive longer?

A. Using mulch and watering at the base of the plants with soaker hoses will help. Overhead irrigation, such as with sprinklers, can splash disease spores from the soil to the leaves of our plants or from leaf to leaf or plant to plant. Watering from below helps reduce the spores splashing. Mulch also helps to keep the separation from the soil where the spores are. Fungicides, such as a copper fungicide, could also be used if desired. Make sure that cucumbers are listed on the product and follow the PHI (Pre-Harvest Interval) for length of days to wait from application to harvest.

12. A caller has spiny vines growing up the trees in her windbreak. How can she kill the vines and not harm the trees?

A. You can go through and cut off the vines and follow that up with a stump treatment using either 2,4-D or a glyphosate product, such as Roundup. Use the concentrate and just paint it on to the freshly cut stump for best control. Do NOT use Tordon, that will likely kill the spruce trees, and it is against label directions. When cutting the vines off at the base, they will stay in the tree but they will die because they have no roots. Treating the base of the plants will kill the roots to eliminate the problem with regrowth.

13. This caller has a patch of asparagus is not doing well this year. He recently piled logs nearby the patch. Would those logs be causing a problem with the growth of the asparagus? The logs are about 3 feet from the asparagus.

A. The logs shouldn’t be causing a problem from that distance, there isn’t black walnut in the wood piled there. It may just be that the asparagus needs to be fertilized. A general fertilizer can be applied in the spring to help with growth. If the spears are getting spindly now, harvesting should be discontinued. The plant will tell you when to quit harvesting based on the size of spears.

14. A caller has cucumbers, zucchini, and potatoes that have just emerged their first leaves. Should those be covered this weekend with the cold weather that is predicted? Would peonies need to be covered?

A. Yes, those warm season crops that have very tender new growth should be covered for the next few evenings. Remember to uncover them during the day. The peonies should be fine, but a freeze could damage the developing flower buds depending on how cold it gets, how long it stays that cold, and how far developed the buds are.

15. This caller asked how to spray her apple trees to prevent problems with insect and disease problems.

A. Orchard fruit tree sprays will combat both insect and disease problems on fruit trees. Sprays should begin as soon as pink is seen in the buds, but should cease during blooming. Since this caller hasn’t begun spraying yet, it would be fine to just start as the blossoms are falling off the tree. You want to allow the pollinators to come to the tree without harming them, so no sprays should be done while the trees are blooming. This spray should be applied every 10-14 days through the growing season, up until harvest.

16. The final caller of the show has a concolor fir that the needles on the bottom third of the tree have turned brown. What is causing this problem?

A. It was hard to determine the problem with this fir over the air. I asked for follow-up photos to help diagnose the problem.

 

Yard & Garden: April 10, 2020

This is the Q&A for the Yard and Garden show for April 10, 2020. 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 31, 2020. 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: No guest host due to COVID-19 and social distancing

1. The first caller asked when the best time is to transplant peonies?

A. The best time is in the fall. They can be done in the spring though, as well. You may want to mark the depth that they are planted at currently to ensure they get planted at the same depth at the new location. Use some masking tape or some other way to mark their depth now. If peonies are planted too deep, they will not flower.

2. A caller has Austrian pines that started turning brown last year. He was told to spray them with a copper fungicide in the spring, is that correct?

A. This sounds like dothistroma needle blight which is common on Austrian Pines and Ponderosa Pines. This disease will cause the tree to turn brown, typically from the bottom up with brown bands on the needles upon closer inspection. Needle blight is best controlled with 2 applications of copper fungicide, one in mid-May when the new needles have emerged to about half their size and a second application in mid to late June.

He also asked if he can plant asparagus now?

A. Yes, asparagus is a spring plant. It can be planted in April or May. Asparagus should be planted in a trench 6-8 inches deep. The recommendation has always been to cover the crowns with 2 inches of soil at first and wait until they emerge to continue to add 2 inches of soil each time until the soil level is even with the surrounding soil. However, research shows that this isn’t necessary. The asparagus should still be planted in a trench 6-8 inches deep, but it can be completely covered back up right away to still be successful.

3. Is there any herbicide that can be used to control weeds in a pumpkin patch?

A. Unfortunately, the majority of these herbicides for use in pumpkins are restricted use and can only be purchased and used by individuals with a pesticide applicator license. For a general backyard pumpkin patch, mulch will be your best option to manage the weeds before they become established. Hand pulling through the season will help as well.

4. This caller had planted spinach and radish a few weeks ago. They had emerged and then were covered with snow and ice last week. Now the tops have burned off entirely. Will they regrow?

A. Unfortunately, if the entire tops of these plants were killed with no green showing, they will not likely regrow. You can wait a week or so to see if they regrow, but it may be time to replant these crops. If they were small they don’t have very much for reserves left in the roots to get new growth back.

He also has asparagus growing but it is continually very spindly. What can be done about that?

A. When asparagus is small and spindly, it may need some fertilizer to help it grow thicker, larger stalks. A general garden fertilizer can be used now, in the spring or a manure or other type of fertilizer can be used in the fall.

5. A caller has a 7 year old peach tree and very old apricot trees that are in full bloom right now. With the freezing temperatures predicted for the next several days, will they produce fruit this year?

A. It is not likely that they will survive these freezing temperatures at the stage they are at. Temperatures are predicted to be in the low 20’s for several nights starting on Sunday. According to research by MSU, apricots in full bloom will have 10% blossom kill at 27 degrees and 90% blossom kill at 22 degrees. Peaches in full bloom will have 10% blossom kill at 27 degrees and 90% blossom kill at 24 degrees. If we can stay a little warmer, at that 27 degree mark you should still see a good fruit set this year, but if we do get the cold temperatures predicted it is not likely to have much of a crop. To see more scenarios and more fruits, visit the Spring Freeze Damage Thresholds Guide.

6. This caller had broccoli growing in her garden. The foliage was burned by frost, but she had planted the plants in a tin can with the bottom cut out placed in the soil and placed a bucket over the plants during the cold nights. Will the plants survive?

A. There is still green in the stems, so they should come back. Give the plants a week or so to determine if new leaves emerge. If they don’t put on new leaves in the next week, it is likely that they won’t survive and need to be replanted. Broccoli can take temperatures down to 26-31 degrees, so they should have been ok. You will want to make sure that the plants are covered again, overnight, for the next few days while more cold temperatures are predicted. The predicted temperatures are lower than what the broccoli can survive under normal growing conditions.

7. Is it too late to plant peas? Can tomatoes be planted now?

A. The peas are ok to be planted now, but it might be a good idea to wait until after this next week when the temperatures are to get very cold overnight. Peas can only take temperatures down to 31 degrees. Tomatoes are a warm season crop and shouldn’t be planted until the beginning of May. If planted in a wall-of-water or other protective method, they can be planted in late April. I wouldn’t push the plants too much earlier than that because they don’t survive cold temperatures and won’t grow.

8. A caller has a blue spruce tree that is losing the needles on the east, southeast side of the tree. This area that is dying is not on the shady side of the tree. The trees are about 20 years old.

A. This caller sent photos to me after the show. After further discussion, it was determined that the tree could possibly have a few issues that are common on blue spruces. I assume they may have had some spidermites last summer that killed off a lot of the needles as well as needle cast disease. The spidermites can be sprayed off with a strong spray of water that will knock them off and kill them. There are miticides labeled for use on spidermites, but sometimes using pesticides can kill the predatory insects as well for spidermites causing more of an outbreak. The needle cast disease can be treated by spraying chlorothalonil or copper fungicide on the trees. Fungicide applications should be made in May when the new needles are 1/2 to 2 inches in length and every 3-4 weeks as rains continue. For more information on needle cast, view this publication from the Nebraska Forest Service.

9. Should marigolds be planted into containers or directly into the ground for best growth?

A. Either will work just fine. Marigolds will make a good container garden plant or they can be used among your perennials and other annuals in gardens in the ground.

10. This caller wants to know how to keep grass out of the asparagus? When should preen be used if that is an option?

A. Preen will work well on asparagus. Make sure you use the preen that is labeled for use in asparagus. It can be applied anytime in the early spring on established plants. When dealing with newly planted asparagus it would be best to wait until the asparagus has begun emerging from the ground. Mulch will also help with weed management in asparagus. Grass clippings, straw, or wood chip mulch can be used on asparagus. If applied early enough, the mulch can be a very effective weed control.

11. Can preen be used on flower beds?

A. Preen would be fine in flower beds, as long as the flowers in the garden are listed on the label of that Preen product. However, if any of the flowers are annuals coming up from seed or perennials that are allowed to grow through seed dispersal in that garden, the preen will stop the germination of those coming up from seed. Do not use it in areas where you plan to grow via seed.

12. A listener wondered about relocating lilacs. Can it be done, if so when?

A. Yes, they can be transplanted. The fall would be the best time for this.

13. The last caller of the day has some hickory and pecan trees to plant. Can they be planted around a black walnut tree?

A. Yes, hickory and pecan trees are in the same family as black walnut and therefore are not negatively affected by the juglone that the black walnut produces to reduce weeds around it.

He also wondered if a pawpaw tree can be planted around other trees?

A. Yes, pawpaw is best grown as an understory tree with partial shade.

Yard and Garden: May 24, 2019

Yard & Garden blog, 2019

This is the Q&A for the Yard and Garden show for May 24, 2019. 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 2, 2019. 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: Donnie Engelhardt, Assistant Manager of the Little Blue NRD

1. The first caller of the show has what he suspects is foxtail in his lawn. He has used pre-emergent crabgrass control and it has not helped. How can he control it? He is also having trouble with zoysia grass on the east side of his house where this foxtail is growing. What can he do to improve zoysia?

A. If this is foxtail, crabgrass pre-emergent herbicides should work on it. I would assume that it may be something else if that didn’t work. This could be little barley, which is a winter annual weed that would be seeding now while the foxtail would not be yet. Little barley is often confused with foxtail, especially this time of the year. For more information on little barley, visit this article on Little Barley from Turf.unl.edu

As for the zoysia grass not growing, there could be a lot of issues with this. If it is on the East side of the house, it may not be enough sunlight for zoysia. Since this is a warm season grass, it is very crucial that the grass gets enough light and it is warm enough for best growth. Also, fertilization schedules would be quite different from cool season turf. Zoysia grass should only be fertilized in the summer months. Warm season grasses really only need up to 2 fertilizer applications per year, if any. Fertilize in later May-June and again in July-August. If fertilizing in the spring and fall, this can harm the zoysia grass.

2. A caller wants to plant either a peach tree or a cherry tree. Which will be better and do either of them get cedar-apple rust?

A. Neither peaches nor cherries will get cedar-apple rust. If you are planning on planting just one, for the growing conditions in southeast Nebraska, you would have more luck with a cherry tree. Peaches are not long lived in Nebraska due to our weather conditions. According to John Porter, Nebraska Extension Educator, “Peaches often have cracking due to rapid freezing and thawing. It can be pretty severe when the fluctuations are large and often. This leads to the gummosis and also damage/death of branches.  Its one of the reasons peaches aren’t well suited for Nebraska.” If cherry trees are chosen, tart cherries are best. Bing and other sweet cherry types will not grow in Nebraska.

3. This caller wants to know when he can plant his asparagus?

A. Asparagus is typically planted in the early spring with other spring crops such as broccoli and carrots. However, with the weather as cool as it has been, it would still be fine to plant it this year. Get it in the ground soon and make sure that the soil remains evenly moist in the hot, dry part of the summer.

4. A caller has an established wind break but mowing now is difficult. Can he prune the branches up so he can mow under the tree without damaging it?

A. Trimming dead branches around the bottom of the tree would be fine, don’t go too high or it will not be as effective as a windbreak. If the branches are still alive and full with needles all the way to the ground, it wouldn’t need to be mowed because the turf will die under that condition.

This caller also wondered about using a granule on the ground around trees to control bagworms?

A. The granule chemical controls he is referring to would be those containing imidacloprid. Bagworms are not a listed ‘pest controlled’ on the imidacloprid label so it is not a legal practice to use it on them. It is best to stick with chemicals such as Bt or Tempo for control of bagworms. Spray them when the bags are up to 1/2 inch in length for best control. I would assume that will be a little later this year due to the cooler spring.

5. What are the benefits of letting asparagus seed out?

A. Asparagus is a perennial crop that needs to have the season of growth to build a bigger, stronger plant. All of our plants need time to grow and build sugars for root expansion. Since we cut off all the asparagus through the beginning of the season, we need to allow them to grow through the rest of the summer.

6. Is it too late to plant strawberries or summer bulbs?

A. It is best to plant strawberries in the early spring. They could still be planted yet this year, but some varieties may not produce this year. Planting this late would cause problems getting the plants established, so be sure to mulch them and water them frequently until they are established. June bearing varieties would be past the bloom time and would not produce this year, but you could plant them to get them established so you can have a harvest next year. If planting everbearing this late, they may still produce later this summer. It would be best to cut off early season flowers that may develop to allow the plants to become more established before harvesting later in the summer after the plants are more established. Summer bulbs are best planted after the chance of frost for the year has passed. You would be past that now and still be in good time to get the bulbs into the ground. It will be later before they start to bloom, though.

green-asparagus-pixabay7. A caller wanted to know what type of manure would be best for asparagus fertilization?

A. Cow, chicken, or pig are good manure options for the vegetable garden, asparagus included. Fresh manure should be applied in the fall to allow time for the bacteria in it to break down before harvesting. For food safety guidelines, fresh manure needs to be applied 120 days prior to harvest, which means the fall in Nebraska. If it is composted manure, it would be fine in the spring.

8. This caller has apple trees. Last year the apples turned moldy while they were still on the tree. What would cause this?

A. There are a lot of different types of diseases that can lead to moldy apples. It could be from apple scab, sooty mold, powdery mildew, or black rot. Using an orchard fruit tree spray through the season would help reduce these diseases. Also, be sure to clean up infected fruits and leaves at the end of the season to reduce the incidence of disease from one year to the next.

9. A caller wants to transplant some foot-tall cedars from his pasture. Is it too late or can this still be done now?

A. It is getting quite late in the year to transplant trees. The concern is for when the shift from spring-like weather to summer hot, dry weather will occur. Typically June starts getting very hot and dry and a newly transplanted tree would not have any root system to get water if it gets dry. It might be better now to wait until fall, September or October. If the trees will be moved to a location where they will be watered adequately, it would be ok, but for best results now, it would be advised to wait until cooler temperatures return in the fall.

10. This caller has a lawn that is thin and weeds are starting to take over. When should he reseed this lawn? Would it be better to just kill it all off and start from scratch?

A. At this point in the year, it would be best to wait until the fall to overseed or reseed lawns. The turf will come up but it will likely get too hot and dry for it this summer, which will be here before we know it. It would be best to just overseed and thicken up the grass that is already established rather than kill it all off and start over. Starting from scratch takes a lot of time and it can be quite difficult. It would be easier to already have something covering the ground while you overseed to keep the weeds down. If weeds are a problem, you can use a mesotrione product, often found in Tenacity, at seeding this fall to kill the weeds when you overseed.

11. A caller wants to know if you can prune a magnolia now to reduce growth? Also, can the suckers around the base of the tree be removed now?

A. Yes, the magnolia hasn’t produced flower buds for next year yet, so it would be fine. Suckers can be removed anytime through the season. Suckers are growth that takes energy from the tree and have no real purpose so it would be best to remove those as they grow before they get too big.

12. Can a bee house still be hung outside yet this spring or is it too late to get much activity?

A. Yes, you would still be fine. These solitary bees are still out moving around. For next year, it would be better to have it out in April. For information on building your own solitary bee hotel, visit this NebGuide

13. The last caller of the day has apricot trees that are just for wildlife consumption. These fruits have not yet fully developed but many of them fell to the ground in storms recently. Her dog is now eating those fruits that have fallen. Is that toxic for dogs to eat them?

A. After discussion with a local veterinarian, the pit is the part of the apricot or peach that would be toxic to the dogs. If these are immature apricots, the pit would not be developed and it shouldn’t harm the dogs. That being said, it might be best to clean up these dropped fruits to be safest.

Asparagus!

green-asparagus-pixabay

Spring officially began last week. That doesn’t mean we should get overly excited and go clean up our beds just yet, this winter has been long and cold so don’t get too ready for spring. However, Asparagus will soon be emerging from past years plantings and new plantings can soon be started.

Planting

Asparagus is a perennial vegetable that will come back every year providing you with more spears without having to plant it every year. Asparagus is planted as crowns in the spring as soon as the soil is dry and can be worked. This year we may have to wait a little longer before planting to give the soil time to dry out after all this snow and rain. Once planted, it is best to wait to harvest from the plant until the third year of growth. Light harvest can be done in the second year, but not all of the spears and not for a long period of time. Asparagus can be planted from seeds, but it will add one more year to the establishment period before harvest is initiated. It is best to give the roots time to become fully established before you begin harvesting. This allows the plant to grow better for a longer life.

Weed Control

Weeds are one of the most common problems for gardeners who grow asparagus. For years, many gardeners used the salt water from making ice cream around the asparagus. Asparagus is a salt tolerant plant and will survive if salt is placed around it and the weeds would die. However, asparagus will not thrive in a high salt condition and the salt can build up and cause asparagus to die over time. Also the salt content in the soil can create a crust which blocks water absorption into the plants which causes drought stress. It is not a recommended practice for weed control.

The better option for weed control in asparagus would be to use mulch around the plants. Any type of organic mulch will work for weed control around the asparagus including grass clippings, wood chips, straw, or hay. This organic mulch will keep the weeds down as well as hold onto moisture and add nutrients back into the soil as the mulch breaks down. Frequent, light shallow cultivation can be done early in the spring will help with weeds as well. Also, use preen that is labeled for use around the asparagus with the mulch to help with annual weeds.

Another tactic is to use a glyphosate product over the bed after the last harvest of the year. As long as the spears have all been cut off at the end of the growing portion of the season and there is no foliage or any green growth above the ground, the glyphosate will not harm the asparagus. Spray the glyphosate over the bed in the late spring when harvest is complete for the year. This will control the perennial weeds as well as the annuals. The spears will then grow back and not be harmed by the glyphosate. Follow up with preen and mulch to keep the weeds out.

Harvesting

Harvesting can be completed by cutting or snapping spears off of the plant as they emerge and grow to 5-8 inches in length. Either method of harvest is fine, I prefer to snap the spears to avoid spreading any disease problems with a knife that just harvested a diseased plant. Snapping is typically preferred by home gardeners. Harvest for 6-8 weeks or until the majority of the spears are less than 3/8 inches in diameter. When all the spears get spindly, the plant is running out of energy for production and harvest should be concluded to allow the plant to rebuild its resources for next year.

Yard and Garden: July 20, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for July 20, 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: John Porter, Urban Agriculture Program Coordinator for UNL Extension and Nebraska College of Technical Agriculture (NCTA)

1. The first caller of the day has holes in her yard that are 1-1.5 inches across. Is this ground squirrels? How can she control them?

A. This does sound like damage from ground squirrels. Ground squirrels can be controlled through trapping, baits, or toxicants. For more information on controlling ground squirrels, visit this guide from UNL Wildlife.

2. This caller has Virginia creeper that is having some issues. The first set of leaves have rust spots and holes on them and the new leaves are showing up but the buds are not opening. This plant is growing in part sun. What is wrong with it?

A. This could be a fungus on the leaves of the Virginia creeper that is leaving a shot-hole appearance behind when the dead areas of the fungus get dry and brittle and fall out of the leaf. If it is a fungus a copper fungicide or chlorothalonil to control it. There could also be some heat stress occurring causing the new leaves to not open up. There is also a possibility that herbicide drift has also occurred that has caused the leaves to not open up.

Harlequin Bug, Alton N Sparks, Jr, Univ of GA, Bugwood
Harlequin Bug photo from Alton N. Sparks, Jr., University of Georgia, Bugwood.org

3. A caller has horseradish with bugs on it that are beetle-like and are black with orange spots on them. What are these bugs and how can they be controlled?

A. These are most likely Harlequin bugs. They can be found on horseradish and they can do a great deal of damage. Harlequin bugs are a true bug, like a stink bug, They suck the juices out of the leaves of our plants leaving them wilted and discolored. They can be managed with the pesticide sevin.

4. A walk-in listener works with the football field in town. They have brown spots throughout the field and have found some caterpillars and a large amount of tiny, worm-like creatures. What are these? What is causing the brown spots? How can these problems be solved?

A. These caterpillars are sod webworm. They are a pest of turf. These caterpillars can cause brown spots in the lawn. Triazicide is labeled for sod webworms and would give pretty quick knockdown. The worm-like creatures found on the lawn could be nematodes or they could be fungus gnat larvae. Fungus gnat larvae rarely cause serious damage outside.

5. This caller is having difficulty with tomatoes ripening. What is the problem?

A. The hot weather is causing poor pollination. The pigments responsible for the red color in our tomatoes are not produced when the temperatures exceed 85 degrees. So, when we see long stretches of very hot weather, our tomatoes will not ripen. Be patient, they will ripen eventually when the very hot temperatures recede.

6. A caller is having problems with weeds in his asparagus. Will preen work now to control the weeds? Also, does he need to water his asparagus in the winter months because his asparagus isn’t growing very well.

A. Preen should be applied in the spring to control annual weeds, it will not do anything to control weeds that are already growing in your asparagus. At this point, hand pulling and applying a layer of mulch would be the best option for managing the weeds in the asparagus. When the asparagus is cut back this fall or before it begins to grow in the spring, glyphosate (Roundup) can be used to control the weeds. The glyphosate product can be used directly over the asparagus patch as long as no green from the asparagus is growing above the ground. Then, apply a layer of preen (make sure it is labeled for use in the asparagus) and add the layer of mulch.

Bagworm4
Bagworm

7. The last caller of the day has bagworms in their windbreak. The bags are 1-1.5 inches in length. What should they do about these?

A. Pesticide sprays for bagworms are not going to be as effective now. It is better to control the bagworms from when they hatch until they are up to 1 inch in length. Spraying a chemical now would kill some, but the rate would not be nearly as effective as before. It might be better to just handpick the ones you can reach and watch for it next year to be able to spray sooner in the season when it is more effective.

Yard and Garden: June 29, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for June 29, 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: Roch Gaussoin, Extension Specialist from UNL

1. The first caller of the day has green worms on her tomato plants. How can she get rid of them?

A. This is a tomato hornworm, a common pest in vegetable gardens. Tomato hornworms can easily be controlled by picking them off and throwing them into a bucket of soapy water or sprayed with sevin or eight.

2. A walk-in listener has buffalograss that is turning a reddish/brown color and dying in patches throughout the lawn. What is wrong with the lawn?

A. This is a disease called bipolaris leaf spot disease. The lawn should grow out of it. Adding 1 pound of Nitrogen fertilizer per 1,000 square feet would help reduce the problems with this disease. Check the lawn for chinch bugs as well, if they are also found, treat for them with insecticides.

This listener also wondered if his lawn should be mowed?

A. With buffalograss, it depends on what you desire from your lawn to determine whether you mow or not. It will be beneficial to mow the lawn at least once per year. Mowing one time per month will help thicken up the lawn overall for a better, fuller look.

3. A caller has poison oak growing up a tree. The root is next to the trunk of the tree, can it be cut off and the stump treated with Tordon?

A. Do not use Tordon in this situation. Tordon is not labeled for use in a landscape setting and it would likely kill the tree as well due to the proximity to the roots of the weed. Tordon is a mobile chemical and it can get from one root easily to another. It would be best to get the weed identified first as well, poison oak is not common here in Nebraska. It is likely that it is woodbine or poison ivy. Woodbine is not harmful to the tree. If still desired to kill the vine, use the “glove of death” which is when you wear a chemical-resistant glove and then put a cloth glove over that. Then, dip a few fingers of the gloved hand into Brush killer or Glyphosate and rub those fingers along the stem and leaves of the undesired plant to kill it.

4. This caller drilled a grass prairie this spring. Now, the grass really isn’t growing, it is mainly weeds. Should he mow it now or how can he proceed to get the grasses growing and kill off the weeds?

A. It is common for new prairies to struggle for the first 1-2 years. Mowing will reduce the weed presence and will thicken the stand of grass that is present. Be patient, it just takes time to get these native grasses really growing.

5. A caller has wild asparagus that he would like to move. When is the best time to transplant it?

A. Spring would be the best time. However, it would be more beneficial and less work to just kill off the asparagus that is growing in the wrong location and planting new crowns in the new location. There are newer, better, hardier varieties available now. Transplanting does not speed up the time to harvest over new crowns. Either way, transplanting or planting new crowns, it is recommended to wait 3 years before heavy harvest of the asparagus to ensure the roots get growing well before harvest begins.

6. This caller planted poatoes, corn, tomatoes, and onions. The leaves are now curling on some of the plants. They added horse manure this spring for compost. Did the manure contain herbicides that are now causing the damage?

A. This could be herbicide drift from nearby fields. Herbicides could be a contaminant in fresh manure, not as likely through composted manure. Be careful when using manure for food safety measures. Fresh manure should never be applied right at planting time. If using fresh manure, it should be applied in the fall to ensure any harmful bacteria breaks down before plants produce fruit that could come in to contact with the bacteria in the soil. Composted manure can be applied in the spring at planting because the composting process would break down the bacteria.

7. A caller planted 35 blue spruce trees this spring. Do they need to fertilize them? Do they need to water them?

A. Fertilizer is not necessary. Typically in Nebraska soils, the main nutrients for tree growth are found and are accessible. Water the trees about 1 inch of water per week. If we are not receiving that through rain, it needs to be given through irrigation. A soaker hose or sprinkler or even a 5 gallon bucket with a small hole drilled in the bottom would work to irrigate these trees.

8. This caller has grasshoppers in their garden and plans to spray sevin for them. Is there a better time of day to spray for grasshoppers?

A. Grasshoppers can be sprayed at anytime of day. However, it is important to spray grasshoppers while they are still small, they are easier to kill when they are younger. Also, make sure to spray the roadsides and ditches where the grasshoppers tend to congregate as well as the areas where they are damaging your plants. For more information on grasshoppers, see this Guide to Grasshopper Control in Yards and Gardens

9. How do you manage ground squirrels in the lawn?

A. Trapping is most effective. For information on 13-lined ground squirrels and how to manage them, check out this NebGuide.

10. A caller has poppies that are growing wild in her gardens. What can be done to control them?

A. Spot spray or carefully paint herbicide on the leaves of the poppy plants or use the chemical-resistant glove, cloth glove method listed in question #3. Roundup would be ok for this time of year. 2,4-D can be used in the fall, but not now with fear of volatilization to your garden plants.

This caller also asked how to move volunteer cedars that are coming up throughout her lawn? She wants to add them to her deteriorating windbreak.

A. Cedars are fairly resilient and easy to transplant. Since they  are still small, just dig up the small trees and get as much of the root as possible and replant them in the desired location. It would be better to wait until the fall to do this because moving them now will be hard to keep them alive in the heat of the summer. Make sure to keep the plants watered well throughout their transition period. They don’t need much water but would need it more often if they are very small because they don’t have a large root system.

2018-06-29 11.05.53
Purslane

11. Another walk-in listener has a fleshy weed that they found in their garden. What is the weed and how can it be controlled?

A. This is purslane. It is a common weed in our lawns and gardens. Purslane easily reproduces from cuttings so avoid hoeing or weed trimming through it while leaving pieces of the plant laying around on the ground throughout the garden. Purslane doesn’t like to be smothered, so a heavy mulch layer on the weed will help.

12. A caller passing through on the road wants to know how to control trees in pastures? They have been trying using 2,4-D with little success.

A. Cut off the trees and do a stump treatment with something stronger than 2,4-D such as a triclopyr product which is found in the brush killers. In a pasture, you could use tordon in this scenario to control the trees. Don’t use tordon if there are other desired broadleaf plants such as wildflowers or other trees nearby.

13. This caller has an Autumn Blaze Maple that is turning yellowish. He applied iron granules but they don’t seem to have much of an effect on the tree. What can be done?

A. Trunk injections of iron work better than granules. The trunk injections will also last for 4-6 years rather than just one year with the granules. Trunk injections of iron need to be done by a certified arborist.

14. A caller has potatoes that are growing on top but are not developing tubers. Not all varieties are affected the same. What is the problem?

A. The quick transition from cold to hot and the long-term heat this summer may have caused the plants to not produce the tubers as well. Some varieties may be better suited to deal with the heat which would explain the differences between varieties.

15. The last caller of the day wants to know if Linden would be a good replacement for Ash trees as the Emerald Ash Borer moves closer and when to transplant cherry trees?

A. Linden is a great replacement tree for ash. It would be a good idea to start the linden nearby now and remove the ash when it dies or when the linden begins to take off. Transplanting trees is best in the spring or fall. So for this year, wait until mid-September or later.

Yard and Garden: June 22, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for June 22, 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: Kathleen Cue, Dodge County Extension Educator

1. The first caller of the day has cauliflower that is turning purple in the garden. What is causing this and can it still be eaten?

A. This is a response to the heat. For next year, blanche the heads just after they begin to form by tying the large leaves up around the cauliflower heads to protect them from the sun or purchase self-blanching varieties. This cauliflower can still be eaten even though it has turned purple.

2. When is the best time to move asparagus?

A. Spring would be the best time for planting asparagus. It is more beneficial to just start a new asparagus patch rather than transplanting. It would be difficult to get all of the plant and there are a lot of newer varieties that will do better with heat and other conditions. If you transplant what you already have growing, it is still best to wait 3 years before heavy harvest again, so it would be beneficial to start over since this asparagus bed is already 20 years old.

3. A caller has nutsedge in their lawn, how can it be controlled? Roundup didn’t seem to work for it.

A. Roundup would not be effective in this situation because roundup is for grass control, while nutsedge is a sedge. For best control of nutsedge, it is best to use either Sedgehammer or Tenacity. Both of these chemicals should be effective, but they should be applied prior to the first day of summer to reduce the population for next year. Also, nutsedge tends to grow in areas of the lawn where the soil is compacted or water tends to sit, reduce the compaction and get the turf growing better to control the sedge better.

Yellow Nutsedge-Howard F. Schwartz, Co. State Univ, Bugwood
Nutsedge photo by Howard F. Schwartz, Colorado State University, Bugwood.org

4. This caller has a few walnut trees that the tops look good, but near the base of the trunk the tree is losing bark. He recently added some soil and river rock around the trees. Will the trees survive?

A. When adding soil and rock around a tree that had been planted for a while, it changed the grade around the trees. This can lead to many problems with the tree because it makes the tree too deep in the soil, especially after the roots were at a higher level in the soil for multiple years. This will lead to the death of these trees. The bark could be coming off because of the death beginning in the tree or it could be due to possible damage to the roots when the soil and rock was moved in. Either way, the trees will die. Enjoy them until they do or until they become a hazard to homes, cars, or people found underneath them.

5. What would be a good replacement tree for scotch and Austrian pines?

A. Diversity is a good thing to remember when planting a new trees. Diversity includes species and age of trees. This caller has a great deal of trees to replace in a CRP, it is advised to not replace all of these trees at the same time so they have a diversity of age as well. Good choices include Douglas fir, concolor fir, hemlock, eastern red cedar, blue spruce, black hills spruce, Norway spruce, and Ponderosa pines.

6. A caller has a windbreak with bagworms. Is it too late to spray this year? What should he spray with?

A. We should be ok in the window to spray for bagworms. It is best to spray after the bagworms have germinated for the year until when the bags have developed over 1 inch in length. Once the bags are larger than 1 inch long, the chemicals will not be very effective. Tempo or Bt products would be the best choices for control of bagworms, but most any general insecticide will work.

Bagworm4
Bagworm

7. This caller has a 20-year-old red maple that only has leaves on the west side to cover only 1/4 of the tree. What is wrong with the tree?

A. When that much of the tree has died back, it will not recover. It should be removed to reduce the hazards that will appear from a dead tree.

8. A caller has a newly planted blue spruce. How long should they maintain watering the tree? Should it continue through the winter months?

A. Newly planted trees should be watered throughout the growing season, and even during the winter. If we don’t have a lot of snow cover through the winter months, it is important to water an evergreen tree about once a month on a warmer day. When watering in the winter, water in the early to mid-day to allow all of the water to soak into the soil rather than freeze up on top. It would be best to continue watering this tree at least for 3-5 years on a regular basis. However, even a 30-year-old tree needs to be watered some in years of drought. It would be best to always continue to water this tree, even if only sporadically.

9. This caller wondered if adding drain tiles when adding a raised bed around an established tree would help it to survive with this practice that is not recommended?

A. Adding a raised bed to an existing tree is not an issue with drainage. Adding more soil to where a tree is already living can decrease the amount of oxygen that the roots are able to get which can then kill the tree. Also, adding this soil make it so that the trunk of the tree is underground which can decay the trunk and lead to crown rot or other bad conditions that also lead to death of the tree.

10. A caller has a pin oak that the roots are starting to pop out of the soil around it. What can be done for it?

A. Wood-chip mulch can be used to cover up the roots as they show up out of the soil. Do not add soil or increase the soil level. Avoid rock mulch as it can be too hot for the plant. Adding a mulch over the roots will prevent you from mowing over the roots and injuring them. Plants can be planted among the roots as well, but don’t add soil to do that.

11. Is it too late to prune lilacs?

A. Lilacs will begin producing flower buds for next spring shortly after they finish flowering this year. They should be pruned within a couple of weeks after blooming has finished in the spring. They can be pruned this late, but it will reduce the flower production for next year.

12. This caller has lilacs that have never been pruned for many years. How, when, and how much can she prune now?

A. A rejuvenation pruning may be beneficial for this situation. Older lilacs, if never pruned, have unproductive wood. This will lead to less leaf production, less flowering, and often much of the leaf and flower production will be just at the top 1/3 of the plant. When this happens, it is best to just prune the lilac off 6-8 inches above the ground to allow it to regrow with younger, more productive wood to produce more leaves and flowers throughout the whole plant. Rejuvenation pruning should be done just after flowering or in the fall for best health of the plant.

13. The last caller of the day wants to know about planting and growing blueberries and currants in Nebraska. He has pots he wants to plant them in to plant the pot into the ground. Is that necessary? What type of soil should be used?

A. Blueberries are not the best option for Nebraska soils. They must live in highly acidic soils, which we do not have. If determined to grow blueberries in Nebraska, it is best to grow them in a pot in the ground that can be brought up every year to amend the soil with acidic fertilizer or peat moss. Serviceberries may be a better choice to blueberries for Nebraska. Serviceberry is a native plant so it will grow in our natural soils with a lot less care and they have more antioxidants than blueberries do. There are also some newer varieties that have berries larger than blueberries. Currants will grow just fine in our natural soils and need no ammendments.

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.

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.

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.