Yard & Garden: May 15, 2020

This is the Q&A for the Yard and Garden show for May 15, 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 wants to know how to plant the flowering plants he received from the Lower Big Blue NRD in Beatrice on the show last week? How far apart to space them and what type of growing environment should they be planted in?

A. Give the plants plenty of space, they are all large shrubs or small trees. The selection included Nanking cherry, redosier dogwood, lilac, crabapple, and caragana. They all need at least 8 feet of width and height. They all take full sun, but the redosier or red twig dogwood can take part shade. They could be planted on the interior of a windbreak to add to it or throughout a landscape.

2. A caller received a hydrangea plant as a gift for Mother’s Day. The flowers are now droopy. Should it be planted outside or what can be done to improve the flowers?

A. Yes, plant it outdoors. It can be planted in a container, but that would need to be protected over the winter months. Otherwise, plant it outdoors in part sun. The plant may also be finishing up the bloom period for this year, so remove those spent blossoms when they begin to turn brown.

3. This caller has iris borer. Should she dig up the plants now to remove the highly infected, mushy areas?

A. Leave them for now but clean out the mushy rhizomes as much as you can and spray the plants with an imidacloprid product to kill the larvae. Dig up the plants in the fall and clean them out. Next spring spray the plants earlier to prevent more damage. Also, be sure to clean off the dead leaves in the fall, this will destroy their overwintering location.

4. A caller has strawberries with a leaf spot disease. What can be done with them? He is already harvesting.

A. To prevent further spread and reduce diseases in the future, use soaker hoses to water rather than watering over the top of the plants. Also, make sure you have mulch around the plants which can also help reduce the spread of diseases. Captan can be used through the season for leaf spot disease. Spray every 10 days through the season, next year start before they begin to bloom. Be sure to follow the PHI listed on the product for strawberries. The PHI is the Pre-Harvest Interval, the amount of time to wait after applying a chemical before harvesting.

5. A caller has cedar-apple rust on his cedars that is harming them and causing the branches to turn orange. What can he do for it?

A. Cedar-apple rust is not damaging to cedar trees. If the branches are becoming covered in orange, it could be cedar-quince rust which can cause problems on cedar trees. You can spray the trees with Captan, Daconil, or Mancozeb to treat cedar-quince rust.

6. This caller has beans and popcorn that was planted from seed a while ago but it has not sprouted yet. Why is that?

A. It has been too cold for them yet. The soil temperatures are hovering just below 60 degrees and most of our warm season plants need at least 60 degree soil temperatures to grow well. Give them time, they should sprout in the next week or so as the weather warms up more.

7. A caller has Elephant Ear that was in the garage over the winter. She planted it in a lick tub before the last weekend with the cold temperatures. It has not yet sprouted, will it be ok or is it likely done?

A. It is still quite chilly for something like an elephant ear. Even though the plant had not yet emerged before the frost events last weekend, the lick tub may not have protected it enough since it is a bulb that needs to be dug up every year. Give it time, it might be ok though. It is hard to tell for sure yet.

8. This caller has wild violets in her yard. She had it treated twice in the fall and they are still coming up. What can be done about that?

A. Wild violets are very difficult to manage. They cannot be eliminated in a single treatment or even in multiple treatments in one year. It will take time and reapplications to really knock them back. 2 applications in the fall will be most effective. Apply a 2,4-D product in mid-September and again in mid-October for best control. Because we don’t know when the lawn was sprayed, or exactly what was spryed on it, it is hard to tell for sure why the plants are still so bad. Diligence with this plant would be best.

She also wanted to know how to control nutsedge in her lawn.

A. Nutsedge can be controlled with a sedge-specific chemical such as sedgehammer or sedge ender among others. Apply these chemicals before the longest day of the year, June 21st, to help reduce the population for next year. It isn’t a preemergence herbicide, but it will reduce the growth for future seasons.

Her final question was how to control weeds through the summer in an area that she has planned to overseed this fall?

A. Keep mowing the area will help reduce the flower and seed production through the year. She can continually spray roundup on the area throughout the summer to keep them down as well. Spray the Roundup 2 weeks ahead of overseeding to help kill it off before planting. She could use mesotrione, found in Tenacity, at seeding to help with weeds and not harm the seeding.

9. Why are the peonies not blooming yet?

A. With all of the cold weather we have had, it has slowed the growth of plants such as peonies. They are behind their normal blooming time for the year due to the snow and frost so late this spring. Give them time to flower a little later. They likely will not bloom by Memorial Day this year because of how cold it has been this spring. However, depending on the stage of development of the flowers when the snow and frost occurred, the blooms may have been damaged and may not open up this year. Give the plants time to recover into mid-June before giving up on the blossoms.

10. This caller is trying to grow rhubarb. It will start growing in the spring but then just stops growing larger and isn’t getting very large stalks. What is the problem?

A. It might be good to try a soil test to see how the soil nutrient levels and pH are where the plants are growing. You could try some fertilizer to help it grow larger. These plants were purchased from a flea market, from another grower, it might be that the plants were older and maybe not as productive. Try to start a new patch with new plants purchased from a nursery or garden center.

japanese beetle JAK582
Japanese Beetle, Image from Jim Kalisch, Retired from UNL Entomology

11. A caller has linden trees that had a problem with Japanese beetles last year. What can be done to control them this year?

A. After they have finished blooming, the trees can be sprayed with bifenthrin or chlorantraniliprole. Make sure you can get to the top of the tree for best control. He may need to call an arborist to spray the trees more thoroughly. Treating the yard for grubs can help. Don’t put a trap in your yard, this just brings more in from the surrounding locations.

12. This caller is wondering why her iris’ are not blooming? The plants of the same variety are blooming on one side of her house but not the other. Why is that?

A. The cooler weather is causing many of our plants to slow down or not bloom when they normally would be blooming. If the iris are blooming on one side of the house and not the other, and they are the same variety, this could be due to the microclimate on the sides of the house. One side may warm up sooner in the day causing those plants to warm up more and bloom sooner. Maybe the wind is hitting the one side more causing those plants to stay cooler longer. Give them time, they should all bloom eventually.

She also wondered why her celery is yellow. Is it due to the cold damage or is she overwatering?

A. It could be due to the cold weather. She is watering every other day for 2 hours per day with a sprinkler, this could be too much water. Monitor how much water is actually applied during that time by using a catch can. Vegetable gardens need about 1 inch of water per week. I would assume this celery is getting more than that.

13. Why are there so many seed stalks in the rhubarb plants this year?

A. The cold temperatures this spring are unusual and have “confused” the plants. This has pushed the plants to produce seed stalks. When rhubarb plants begin to produce seed stalks they push their energy into seed production and not into leaf and stalk production. To push that energy back into the stalk production we desire from rhubarb, cut the seed stalks off of the plant.

14. The final caller of the day has onions that are turning white and falling over. He didn’t cover them in the freezing weather last weekend. Is it cold weather injury that is causing this damage?

A. It is likely that this is from the cold temperatures. Even onions can be injured by temperatures in the low 30’s like what we saw. If there is green in the lower leaves, they might regrow.

*Reference to commercial products or trade names does not imply endorsement by Nebraska Extension or bias against those not mentioned.

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: May 1, 2020

This is the Q&A for the Yard and Garden show for May 1, 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 day has a plant that comes up in his grass, he calls it onion weed. They have tried 2,4-D products but it is still alive and keeps coming back and spreading. What is it and how can it be controlled?

A. This is likely wild garlic or wild onion due to the onion/garlic smell of the leaves when you break them. They are very difficult to control in the lawn. Multiple application of post-emergence herbicides such as Roundup or 2,4-D products. If using the roundup you will need to reseed the area as roundup will kill all plants, including the turf. You can also dig them up as you see the patches appear. It is best to mow just prior to spraying but not mow for a couple of weeks after spraying.

2. This caller has something that is boring holes in his yard. There are a bunch of holes in the yard that are 1 inch in diameter with very fine soil around the holes. What would cause this?

A. There are a few options for this. He wasn’t sure how deep the holes went but didn’t see any runs in the lawn around the holes. Without a few images of the damage it is too difficult to give a definitive answer.

3. Is it too late to start spraying peach trees for insect and disease damage?

A. To have a peach tree on a spray schedule with an Orchard Home Fruit Tree spray, it is best to start when the buds begin to open up and show pink behind the sepals. Then, you would spray every 10-14 days through the growing season except during the bloom period. This will help with insects and diseases. If you didn’t get started before the bloom, you can start now that the tree has finished blooming.

4. A caller has hostas that have grown very large and thick. Can they be divided?

A. Yes, now would be a good time to dig them up and divide them. They can be divided in half, thirds, or quarters depending on the size of the plant. After they have been divided, replant them, make sure to space them out correctly. Keep them well-watered once replanted because they will have a limited root system.

5. This caller is curious about catchweed bedstraw and what to do about it.

A. This weed is found throughout our landscapes. It is a winter annual weed like henbit. It can be pulled very easily because it has a very shallow root system. You can also spray it with a 2,4-D product or Roundup.

6. A caller is wanting to plant tulips in his landscape under a tree. Would this be a good location for them and do you need a lot to get good coverage under the tree?

A. Yes, tulips will grow well under trees but you do have to plant a lot to get a good effect from them. They should be planted in the fall, such as early October.

7. What can be done about moles in the yard?

A. Trapping can be used on moles. It is most effective using a Harpoon type trap and if you prepare the area prior to setting the trap. Find an active run by stomping it down a few times before setting the trap. If the run continues to pop back up, set the trap there the third or fourth time you stomp the run down. This should ensure get the mole. For more information view this NebGuide.

8. This caller has 2,4-D that froze in the container. How can he get rid of that?

A. If you can find a pesticide disposal location, that would be best. However, if you cannot find one, the best way to dispose of pesticide is to apply it to a labeled site (specific plant, animal, or structure) for which the product is registered. Always double check the product label to be certain that the site is listed and that the maximum application rate will not be exceeded.

9. The final caller of the day wanted to know how to get pampass grass to spread. Can it be pruned a certain way to encourage spreading?

A. No, you can’t prune it any way to encourage spreading, it will just take time. Over time it will grow larger to fill an area better or you can divide the plants to spread them out farther, but nothing else will be effective for spreading.

*Reference to commercial products or trade names does not imply endorsement by Nebraska Extension or bias against those not mentioned.

Yard & Garden: April 24, 2020

This is the Q&A for the Yard and Garden show for April 24, 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 day had his yard sprayed for broadleaf weeds yesterday. How long should he wait before overseeding the lawn?

A. According to the label of Trimec, grass cannot be reseeded until 3-4 weeks after applications from the product. Any 2,4-D product would be similar. At this point, it would be best to wait until the fall to overseed the lawn, because that late in the spring would be hard to get the turf established. Be sure to tell your lawn company not to spray it in the fall until after the new grass has been mowed 3 times in the fall.

2. Can you start sweet potatoes from the sprouting sweet potatoes purchased from the grocery store?

A. You can, but they may not grow quite as well as desired. The varieties in the grocery store may not be as hardy as some of the varieties from the garden centers.

3. This caller is planting cucumbers, zucchini, pumpkins and other cucurbit plants. How far apart do they need to be planted to prevent cross-pollination?

A. The cross-pollination affects the produce in the following year, not the current growth period. The produce on the plants this year will be fine, but if they cross-pollinate, the fruits produced next year may not be true to the variety you are saving seed from. They also have to be in the same species to cross-pollinate, and cucumbers and zucchini are not.

4. A caller has rhubarb plants that are producing seed heads. Why is that happening so early and should anything be done about that?

A. The cold temperatures from last week are unusual and have “confused” the plants. This has pushed the plants to produce seed stalks. When rhubarb plants begin to produce seed stalks they push their energy into seed production and not into leaf and stalk production. To push that energy back into the stalk production we desire from rhubarb, cut the seed stalks off of the plant.

5. This caller has a rose garden that has chives coming up among the roses. What can be done to manage the chives and not harm the roses?

A. Among other plants it is best to 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 Glyphosate and rub those fingers along the leaves of the chives to kill it. This will likely take multiple applications over multiple years to completely rid the garden of the chives, but this is best to not harm the roses.

6. A caller is wondering what the best method is for transplanting 5 foot tall peach trees?

A. The best time for this would be in the dormant period, either in the fall or late winter months. Be sure to get as much of the rootball as possible.

7. This caller has planted the Hairy Balls plant and now grass is growing up among the plants. Can Grass-B-Gon be used in these plants to kill the grass and not harm the plants?

A. It should be fine, Hairy Balls plant is in the milkweed family which is not a grass. It would be best to avoid spraying directly on the foliage of the desired plant to ensure limited exposure.

8. This caller started lettuce, spinach, and some herbs before the snow. They have not come up yet. Will they be ok or should they be replanted?

A. Give the plants a little more time to see if they come up yet. If they hadn’t germinated yet, they should be ok, but the soil temperatures were too cold with the snow and freezing temperatures last week for them to germinate. If they don’t come up soon, you can try to reseed or move these crops to a fall garden because we are going to start getting too warm soon.

He also wanted to know if his strawberries will survive? He planted them as roots prior to the snow, and they had no real above-ground growth prior to the snow.

A. Those should be fine, because they hadn’t started to grow yet. The roots should have been protected enough to survive.

9. A caller has strawberries that are growing in a raised bed. The strawberries in the center of the bed seem to have died out. Can she move some new starts from the outside edge to the middle now? Also, what should they be fertilized with? She has some 11-15-11 can she use that?

A. Yes, it is ok to move established plants now to fill in the bed better. The fertilizer she has would be fine to use. Just be sure to follow the label instructions on applications.

10. When can a magnolia tree be pruned to allow a lawnmower underneath?

A. The timing for tree pruning has shifted a little recently due to new research. The International Society of Arboriculture has moved the time frame to correspond with the spring growth flush which would be May through early June for southeast Nebraska. This allows the tree to seal up the wound faster with less disease and insect issues.

11. This caller has snowball bush hydrangea plants that are spreading and growing into the lawn. Can he divide the plants to move the plants that are spreading into undesired areas to grow in better locations?

A. Yes, either do it now or in the fall. When you dig them up, they may be attached to the main plant, just prune that connection off to move them.

12. A caller has iris plants that had pushed new leaf growth and then were hit by the snow and the tips of the leaves are brown and discolored. What should be done with that?

A. The plants will be fine. It might be best to wait until a few more leaves appear that are not brown, then the entire leaf that is brown can be removed. Wait to get more new leaves to avoid removing all the sugar producing leaves to be removed now.

13. What are some good plants for pollinators? Where should these be purchased?

A. Good choices would include butterfly bush, butterfly milkweed, milkweed, goldenrod, coneflowers, bee balm, sunflowers, coreopsis, and many more. They can be purchased at local nurseries and garden centers. Pollinator seed mixes can be found at some seed supply companies, including Stock Seed Farms in Murdock, NE.

14. The final caller of the day planted pampass grass it started to green up, but now after the snow nothing seems to be alive. Will these plants be ok?

A. Give the plants a couple more weeks to see if they will regrow. The roots should still be fine and it is likely that they will regrow, but if nothing in a couple of weeks, there would still be time to replant these.

*Reference to commercial products or trade names does not imply endorsement by Nebraska Extension or bias against those not mentioned.

Yard & Garden: April 17, 2020

This is the Q&A for the Yard and Garden show for April 17, 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 day wants to know when he can transplant the zucchini, eggplant, and peppers that he started in his home this year. With the snow, should he wait a little longer?

A. Yes, these are all warm season crops and they need soil temperatures in the 60’s before they will do much at all in the garden. They also will not live through temperatures below 31 degrees Fahrenheit. Warm season crops should wait to be planted after the last frost of the spring, which averages in late April for southeast Nebraska. It is a good rule of thumb to go with early May for planting to ensure you are past the last frost of the year, I like to use Mother’s Day for a general planting date. With crops started indoors at home, remember to harden them off for a week or two ahead of planting outside. Hardening off can be completed by gradually moving the plants into more sunlight and more wind exposure each day and bringing them indoors overnight.

2. A caller wanted to know where the best location is to plant rhubarb?

A. Rhubarb should be planted in full sun, in well-drained soil. Make sure that it is a location that isn’t low in the landscape or a location where water tends to sit. Rhubarb is very prone to crown rot if not in a high, dry location.

3. This caller has peonies. They had emerged and were about a foot tall. Now, after the snow, they are leaning over. Will they be ok?

A. If they were hit hard by the snow, they may lose a few leaves, but the plant will be fine. Peonies are early season plants and therefore should be just fine through late spring snows and cold weather. Give them time to recover before jumping to cut them off. If the leaves remain discolored or limp, they should be removed in a couple of weeks. The blooms were not set on these plants so they should still bloom.

4. A caller didn’t get his potatoes in yet, when should they be planted? He thought you were to plant potatoes on Good Friday or St. Patrick’s Day.

A. Potatoes are more of a cool season plant, and it is an old saying to plant them on Good Friday or St. Patrick’s Day (depending on who you talk to for your timing). However, this was a rare, high amount of snow and unusually cold weather. They can take down to freezing, but lower than that they might need to be covered to get through. So, if they aren’t planted yet, plant them once the snow has melted now. The weather is supposed to warm up now.

5. This caller is going to be planting strawberries in a raised bed. What materials should he use for building the sides of the bed?

A. Landscape timbers work well for raised beds or old railroad ties that are no longer oozing any creosote. Also, bricks or other hardscaping types of bricks can be used.

6. A caller wants to know who to call to remove an evergreen hedge from her landscape?

A. It would be best to call a professional tree trimmer or tree removal service. A Certified Arborist would be best, but just make sure the company is licensed and insured.

7. This caller has pine trees that have a lot of brown branches throughout the tree. What is causing it?

A. Unfortunately, it is hard to tell from the description. The trees need to first be properly identified to know what type of tree it is and I would need to see what the brown areas look like to know for sure what it is. The caller was going to send photos, but hasn’t yet.

8. A caller has asparagus that came up and was growing but they didn’t cover the plants for the cold weather and snow. Now the spears that were up are soft to the touch. What is wrong and will the plants survive?

A. The freezing temperatures and snow caused this damage. Asparagus is a very cold hardy plant, this is just damage to those spears. Those soft spears should be removed and discarded, but the plant will regrow just fine.

9. This caller has a succulent in the house that was growing well but she repotted it recently because it was getting rootbound. Now part of the plant is leaning over and the leaves aren’t as shiny. It also looks like it has white hairs on it. What is wrong with it and can it be fixed?

A. After looking at a photo and seeing that the plant tag showed this was a kalanchoe, I could determine more about the plant. The white hairs are aerial roots, they aren’t harmful. The plant looks to be leaning for more sunlight. This plant has been in an east window, but needs full sunlight. I suggested moving it to a south or west facing window for more intense, afternoon sunlight.

10. A caller had a vine like plant that looked like cucumber vine last year that took over his windbreak trees. What can be done for it now?

A. This was burcucumber and it was very bad last year. It is an annual weed, so it germinates from seed every year. It does pull very easily, so as you see it start growing up the trees this summer, you can hand pull it. In large shelterbelts, if needed, Simazine (Princep 4L) is labeled for preemergent control in shelterbelts to kill weed seeds as they germinate. Do not apply more than 4 qt. Princep 4L per acre (4 lb. a.i./A) per calendar year. Do not apply more than twice per calendar year.

11. Can you transplant a lilac bush?

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

12. This caller has spruce trees that have mulberries and other scrub trees growing up through the spruces. What can be done to kill these scrub trees and not harm the spruce trees?

A. You can go through and cut off the mulberries 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.

13. When should purple flowering clematis be transplanted?

A. Clematis are best moved in the early spring or fall.

14. This caller wondered about growing vegetable plants in cattle lick tubs. What things are important to know when using these as a container gardens?

A. Make sure there is a few holes for water drainage so they don’t end up soaked after storms go through. Also, the lighter colored tubs will be better than black or dark colored containers. The lick tubs that are black are going to get very hot in the sun, which can be detrimental to the roots of the plants. If you have black or dark colored tubs, you might put some hay or hay bales around the container to help keep it a little cooler. Use potting soil purchased from a store to ensure nutrients and good moisture holding capacity. Don’t use fresh manure at planting around any vegetable plants due to the bacterial issues, manure needs to be applied composted in the spring or fresh in the fall. However, when working with potting soil, no manure would be necessary. Because these plants are growing in containers, they will likely need to be watered more often than a traditional garden. Check the soil every day, if it is dry, water the plants. If the soil is still wet, wait to water. Lick tubs can make very good containers for gardening and could help those who can’t get down on the ground for traditional gardens.

15. A caller has lilies, daylilies, and iris in her flower bed. It got away from her last year and now has a lot of bromegrass growing in it. What can be done to kill the grass and not the flowers?

A. Grass-B-Gon can be sprayed on the garden space. It will kill the grass but not harm the flowers. This would be the only product. It does take time to fully kill the grass, so be patient.

16. This caller has young saplings growing around his garden. Will 2,4-D or roundup work and not harm the garden plants.

A. Yes, either of these products can be used on the saplings and if not oversprayed on the garden, those plants will be fine. Roundup would be the better option when it gets warmer because it doesn’t volatilize like the 2,4-D does. The best way to do this would be to cut the saplings off then paint the herbicide on the freshly cut stump.

17. Is it a good time to apply crabgrass control to the lawn?

A. The snow did push our soil temperatures back down, but they should rebound fairly quickly. I would say in the next week or so we should be back up to the 55-60 degree level to apply the controls. So, go ahead and start using your crabgrass preemergence herbicides.

18. The final caller of the day wants to know when to spray 2,4-D for lawn weeds this spring?

A. That could be done anytime now or in the next couple of weeks. Make sure you apply it on a day that temperatures are below 80 degrees for 72 hours so it doesn’t volatilize and move to non-target plants. Broadleaf weeds are best controlled in the fall once the weeds have begun their preparations for winter. In the fall, these perennial weeds will move sugars that they use for energy from the above ground portions of the plant down into the roots to store them for next spring. If they are sprayed during this phase of their lifecycle, they are more likely to take that herbicide down into the roots to be more effective than if done in the spring. Spraying these weeds in the spring will knock them down, but likely not kill them outright.

He also wanted to know how to store onions?

A. Home gardeners should cure onions after harvest. When the tops are dry, they should be trimmed to 1 inch lengths. Leave the onion‘s dry outer skins on; they help reduce bruising, shrinking and act as an insect barrier. Store onions in shallow boxes, mesh bags or hang them in old nylons in a cold, dry, well- ventilated room. Or braid the leaves of onions for hanging and storage. Temperatures close to 32°F will give the longest storage. Products prone to absorb odors or flavors should not be stored close to onions. For more information, view this NebGuide

*Reference to commercial products or trade names does not imply endorsement by Nebraska Extension or bias against those not mentioned.

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 & Garden: March 27, 2020

This is the Q&A for the Yard and Garden show for March 27, 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: George Pinkerton, Owner of Roseland Nursery

1. The first question of the year was from a caller who has a line of rows and one in the middle died over the winter. He sent in a picture and the yews on either side of this dead one are healthy and green still. What would cause this and will it come back?

A. This could have died from a few different reasons. If winter deicing salts were continually piled up on the roots of this yew and not as much on the others, salt damage can do this type of damage. Too much water can do that as well, so if a downspout sits right next to this particular yew and not as close the other others, that can lead to death like this as well. In the photo, it looks like there is an extension on the downspout to go out past the yew, but water could have ran back toward the yew or the downspout may have recently been added. General winter desiccation can do this as well, but I would think you would see the same damage on at least one of the surrounding plants if it was a desiccation issue. The fact is, though that this yew has died back to the main stem and therefore will not regrow. The yews on either side of it should grow to fill in that gap over time. This dead yew could be replaced if the caller doesn’t want to wait for the others to fill in the gap.

2. This caller wants to know when she should prune her hydrangeas and knockout roses that were planted in 2018?

A. On the roses, it is best to wait until the 3rd year to prune them back heavily. Any dead branches can be removed at any time. However, with roses it is best to wait until mid-April before doing any pruning. Roses have a hollow stem, if moisture gets in that through the freezing and thawing of late winter, it can crack the crown and kill the plant.

As for the hydrangea, it is dependent on the type of hydrangea that you are dealing with. Some hydrangeas bloom on old wood, some on new wood, and some on both old and new wood. The bloom time dictates when it can be pruned to ensure blooms are not removed when pruning. On the show, she wasn’t sure which hydrangea she had, but she emailed me later and it was determined that she had a panicle hydrangea, Hydrangea paniculata ‘Strawberry Sundae’. Panicle hydrangea grows quickly and gets large, so cut it back heavily in spring to shape it and keep it at a good size for the season. It can be pruned to the ground if desired. Or it can be pruned at any height up to 3 feet to create a taller plant. It blooms on new wood, so any new growth shoots will develop flower buds. Prune in spring before new growth starts.

3. A caller is planning on planting strawberries on top of an old storm cellar. What does he need to do to get them started and what does he need to know about strawberries?

A. It would be best if you start with a soil test. With the storm cellar underneath the soil it could have damaging qualities that the strawberries wouldn’t grow well in. The soil needs to be well-drained and have high Organic Matter. Incorporating compost this spring before planting should help with that. When you plant, understand that there are Everbearing and June Bearing strawberries. June berries don’t produce as long but they are larger strawberries than the Everbearing which produce most of the summer but with very small berries.

4. The bagworms were very bad last year. What does a person need to do now to reduce the population for this year?

A. Yes, the population is very high currently. On small trees, this is a good time of year to go out and pull the bags off the tree and smash them or put them into a bucket of soapy water. This is not the time of the year to spray anything for controlling bagworms. They should be sprayed shortly after emergence from the bag, before new bags are more than 1/2 inch in length. The timing for sprays is typically in mid-June, but can be earlier or later depending on the weather. Bt is a great insecticide for bagworms and will not harm many other pollinators, it only affects butterflies and moths. Tempo is a good product for bagworms as well. Make sure you can spray all the way to the top of the tree and get thorough coverage for best control. If you don’t have the equipment to do this, you may want to call a company to spray.

5. This caller has an aspen that is about 2 years old. Last year the tips of the branches and leaves turned black. Now it seems that those tips are dead. What is wrong with the tree and can it be cured?

A. This could be a canker, but it is hard to tell for sure. A picture would be helpful. Canker is a fungal disease in trees that will kill the tree from the point of infection outward on the branch or trunk. It will cause a branch to die or kill the tops of trees, especially in blue spruces.

6. A caller has scotch pines that are about 20 feet tall starting to turn brown, he is concerned it is pine wilt. Is there any control or prevention measures for pine wilt?

A. Unfortunately, pine wilt has no prevention and once your tree has pine wilt there is no control for it. It will kill the tree quickly, usually within 3 months. If one is getting this disease, they will likely all get it. It would be a good idea to start replacing the scotch pines now to begin new growth on different trees. Some good windbreak replacement trees include:

    • Ponderosa Pine
    • Black Hills Spruce
    • Blue spruce
    • White Pine
    • Douglas Fir
    • Concolor Fir
    • Eastern Red Cedar

7. Is it too early to overseed the lawn?

A. It is a bit early for overseeding the lawn. April is a good month, really mid to late April is best for overseeding. If you overseed to soon, the grass could germinate on a warm day, then the tender growth could die overnight on a cold night. The soil temperature is only about 45 degrees currently, turf will not germinate until the soil temperatures reach 50 degrees.

8. This caller wondered when he should prune his trees and what size of branch is too big to remove. He also wondered about a branch that died from bagworms last year. Should it be removed or will it regrow?

Pruning, branch collarA. The recommendations for pruning trees has changed over the past couple of years due to research from the International Society of Arboriculture. The optimum time is early summer, so we are now recommending that you prune trees in late May to early June. It is at this time that the trees are most actively growing, which will allow them to seal up the wound quickest. This will help the trees to have less decay and damage from insects and diseases following pruning. Also, remember it is best to remove branches that are 1/3 the diameter of the trunk or less.

The branch that died from bagworms is not going to regrow. It would be best to remove that branch. Dead branches can be removed at any time.

9. A caller will be planting potatoes soon. When planting seed potatoes, do the eyes need to sprout before planting?  Also, how do you use ashes in the garden?

A. No, when planting seed potatoes, you do not need to have sprouts on the eyes first. You do want to make sure that you cut them apart and let them dry a little prior to planting.

As for the ashes, don’t put too much on a garden. Ash can easily be added at too high of levels which will cause more problems in the garden and make it so some plants will not grow anymore. If you would like to use ashes in  your garden, only apply it one time in the winter months and at a very thin layer. Do not apply wood ash to a garden where potatoes will be planted, it promotes potato scab. Wood ash has a very high pH, it is very alkaline. Our soils are already quite alkaline, so it is likely that it isn’t necessary. A soil test should be done first to see where your pH level is. Most of our garden plants grow in 6.5-7.0 pH, if your soil is already in this level, do not add ashes.

10. The last caller of the day wants to know about using lime on the yard or using fertilizers in general.

A. Lime is not usually necessary on lawns. Lime is used to raise the pH of soils. It is often used in acidic soils, which is not common in southeast Nebraska. A soil test should be done prior to adding nutrients to the lawn, especially prior to adding lime. You can apply a fertilizer application as needed in mid to late April. Wait to see how the lawn greens up to determine if a spring application is necessary. If a lawn has a medium green hue in late April, skip the typical Arbor Day application in favor of one in late May to early June.

Yard and Garden: August 2, 2019

Yard & Garden blog, 2019

This is the Q&A for the Yard and Garden show for August 2, 2019. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am. 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.

Guest Host: Dennis Ferraro, Extension Wildlife Specialist, UNL

1. The first question of the show was about pole green beans. They were planted in May and have been blooming but have not produced any beans yet. What is wrong with them?

A. This is likely due to the abnormal weather pattern we have seen this spring and summer. Make sure that the plants are mulched and watered evenly, as much as you can. Also, the warmer night temperatures will keep the beans from developing.

2. A caller has lilacs that are 2 feet tall. They have rust spots on the leaves. What is causing this?

A. This is likely due to a fungal disease. Make sure you are watering from the base of the plant and keep mulch around the plants. Fungicides can be used but if it is just on a few leaves, just pull those off and destroy them. It also is a little late to spray fungicides on the plants this year. At the end of the year clean up all the fallen leaves from around the plant to prevent re-infection next year.

3. This caller has turf that continually gets brown patch every year, it is only getting one hour of sunlight per day. What can be done to help reduce this problem?

A. Unfortunately, the turf isn’t growing well in this location. Turf is a full sun plant and needs at least 6-8 hours of full sun per day, not dappled light. In this location the turf will always have problems. It might be a good time to switch to another plant underneath the trees. Shade perennials or groundcovers could replace the turf and they would grow much better there. Sedges are another good choice that look very similar to the lawn but would tolerate the shade better.

4. What can be used for weeds in a driveway?

A. Roundup 365 would be a good option for this. It contains glyphosate as well as imazapic which lasts longer than the glyphosate alone. On the label it states to only apply once a year and to “spray until THOROUGHLY WET”, so for best results spray to this extent. Soil sterilants aren’t recommended because they often run off into adjacent plant material such as grass and kills it. You could also use pre-emergent herbicides in the spring to help with annual weeds. Always read and follow the label when using pesticides.

5. A caller has bagworms in his windbreak. What can be done for bagworms now?

A. It may be a little late in the year to treat chemically for bagworms. Once they get much larger than 1/2″ in length, their feeding is reduced and sprays are not as effective. Also, the majority of their damage is done for the year. If you decide not to spray, it would help to go out and pick as many of the bags off as you can and destroy them.

Sandbur, Rebekah D. Wallace, Univ of GA, Bugwood
Sandbur, Photo courtesy of Rebekah D. Wallace, University of Georgia, Bugwood.org

6. How do you control sandburs?

A. Sandburs are an annual grass, so using crabgrass pre-emergent herbicides in the spring will also kill germinating sandbur seeds. Also, sandburs are easily out-competed, so if you can get something else to grow in the area, the sandbur population will be reduced.

7. This caller has Japanese beetles on Linden trees. What can be done to control them? Will the trees die from this?

A. The trees should be fine next year and will leaf out fine. You can spray the trees now with Sevin or chlorothalonil. Next year, you can spray with these products after the bloom period or when the beetles first appear. Do NOT use a systemic insecticide on linden trees due to the high amount of pollinators that are found on lindens.

8. A caller has a problem with squirrels eating his sweet corn. What can be done to stop the squirrels?

A. For a small plot of corn, you can drape bird netting over the corn and use fishing weights to hold it down. From Control of Tree Squirrel Damage NebGuide “Wire mesh fences (no larger than ½-inch weave) topped with electrified wire or mesh enclosures may be practical for keeping squirrels out of small areas. Electrified wires are not recommended for use where there are children or pets. Little else can be done with squirrels in larger areas, other than re-moving the offending squirrels by cage trapping or shooting where safe and legal.”

9. This caller has an apple tree that is covered with Japanese Beetles. She sprayed Tempo on the tree, can she still use the apples?

A. No, fruit trees are not listed on the label. When using pesticides be sure that the plant you are spraying the pesticide on is on the label. With fruits and vegetables, watch the PHI (pre-harvest interval) to know how long to wait between application and harvest.

10. A caller has pin oaks and something seems to be eating the leaves. The leaves are dying and this is a young tree and he is trying to avoid using pesticides. What can be done?

A. This damage could be from grasshoppers or beetles, most of the damage seems to be happening at night so it could be chaffers that are active at night. Using a neem oil or insecticidal soap would work for these pests as an organic option.

11. This caller is having troubles with a groundhog. How can manage the groundhog?

A. Trapping works best for groundhogs. Put burlap over the cage because groundhogs are spooked easily. Use a half an apple or half an ear of corn for bait. Wire the cage open for a few days to allow the groundhog to take the bait and become more relaxed with the trap. Then, after a few days set the trap without wiring it open. Once you catch the groundhog, you cannot translocate it. It must be euthanized with a firearm if legal where you are or take it to animal control. Be sure to check local laws before controlling this groundhog. For more information, visit wildlife.unl.edu

12. A caller is trying to control his bagworms, what chemical can he use for bagworm control?

A. Tempo is a great choice, but sevin or any other general insecticide will work. It may be a little late in the year to treat chemically for bagworms. Once they get much larger than 1/2″ in length, their feeding is reduced and sprays are not as effective. Also, the majority of their damage is done for the year. If you are planning on still spraying, get it done very soon.

13. The last caller of the year called to say “Thank You!” He removed brome grass competition from around his trees, thanks to advice from the show, and now his trees are growing much better.

*Disclaimer ­- Reference to any specific brand named product does not constitute endorsement, recommendation, favoring or implied criticism if similar products are not mentioned by Nebraska Extension in Gage County.  Identifying specific pesticides are for the convenience of the reader and are generally most commonly available.  Always read and follow the pesticide label.

Yard and Garden: July 26, 2019

Yard & Garden blog, 2019

This is the Q&A for the Yard and Garden show for July 26, 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: Bob Henrickson, Horticulture Program Coordinator for the Nebraska Statewide Arboretum

1. The first question of the show was about catalpa trees. They were pruned in the past, but now they have a bunch of smaller branches growing out of the location where the branch was removed from the tree.

A. The branch that was removed was likely not correctly done. If the cut wounded into the trunk of the tree or left a stump, it would cause the tree to push a lot of new growth like suckering. Make sure that proper pruning cuts are followed and that you don’t leave a stump. Follow these steps when pruning a tree to ensure it is removed correctly with minimal damage and avoid the branch-bark collar to avoid a flush cut which will not heal correctly.

3-step pruning cut
Proper pruning cut, University of Missouri Extension

2. How do you control clover in the lawn?

A. Clover can be found in an under-fertilized lawn. It may be a good practice to fertilize at least one time a year to help the lawn compete with the clover. If treating with chemicals, the fall is the best time of year to treat for broadleaf perennials such as clover, dandelions, and creeping Charlie. Apply a 2,4-D product or one containing triclopyr twice in the fall. Mid-September and again in mid-October is best. Other IPM strategies for controlling clover include mowing high and aeration if necessary.

Co Potato Beetle Pupa 2
Colorado Potato Beetle Pupa

3. A question came in via email about orange things on potatoes. There are tiny orange bugs found on potato plants in her garden. What are they and how can they be controlled?

A. These are Colorado potato beetle larvae. Pull any off that are found and smash them or spray with sevin to control them as they emerge as beetles.

4. A caller has creeping Charlie in their yard. When is the best time to spray for that?

A. When using chemicals, the fall is the best time of year to treat for broadleaf perennials such as clover, dandelions, and creeping Charlie. Apply a 2,4-D product or a product containing triclopyr twice in the fall. Mid-September and again in mid-October is best. Other IPM strategies for controlling creeping Charlie include mowing high and aeration if necessary.

5. This caller has cucumber plants with a lot of flowers but no fruits. Why are these plants not producing fruits?

A. You should check the flowers to see if they are all male flowers or if there are female flowers as well. Male flowers just have a skinny stalk behind the flower. Female flowers have a tiny cucumber behind the flower. If male flowers are all that are present, give it time for the plant to produce female flowers. If both male and female flowers are present, there could be a problem with pollinators. Avoid spraying while bees are active, attract bees with other pollinator plants, put up a bee house to bring bees in. If you are using row covers, be sure to uncover the plants for a while during the day so bees can pollinate the plants.

6. A caller called in with a good suggestion to help with cucumber plants. He grows his on a trellis so they can get better airflow and less diseases. It also makes it easier to harvest the plants this way.

7. This caller has a small hackberry that is 12-14 feet tall with 3 trunks growing together. There are small splits all along the trunk like some type of injury, what caused this and will his tree be ok?

A. These could be spots from hail injury, even from a few years ago. There is nothing to do for hail damage. Most trees will come through just fine. If the damage is intense, the tree could have more problems.

8. Is it too late to trim lilac bushes?

A. Yes, it is too late for general pruning of lilacs. They should be pruned within the first couple of weeks following the flowering period. If a rejuvenation pruning is desired, the fall would be a good time to do that, wait until late September to mid-October for that.

9. A caller who manages a golf course has a couple of Linden trees that were under water for about 2 months this year. They sat in a flooded area of the golf course for this time in the spring. They originally did leaf out but since then the leaves have turned brown. Will the tree be ok?

A. There is likely no life left in these trees. Lindens are not adapted to have their roots that wet for that long. The trees probably had enough energy left in the roots to push out leaves but now have ran out of energy. It would be best to remove those trees and replace them with something more adapted to sitting in water from time-to-time, such as bald cypress trees.

10. The final question of the day was sent via email. This listener has a gravel driveway that is partially sloped. How can they keep the weeds out of this driveway and not harm the grass at the end of the slope?

A. Roundup 365 would be the best option for this. It contains glyphosate as well as imazapic which lasts longer than the glyphosate alone. On the label it states to only apply once a year and to “spray until THOROUGHLY WET”, so for best results spray to this extent. Soil sterilants aren’t recommended because they often run off into adjacent plant material such as grass and kills it. Always read and follow the label when using pesticides.

*Disclaimer ­- Reference to any specific brand named product does not constitute endorsement, recommendation, favoring or implied criticism if similar products are not mentioned by Nebraska Extension in Gage County.  Identifying specific pesticides are for the convenience of the reader and are generally most commonly available.  Always read and follow the pesticide label.

 

Yard and Garden: July 19, 2019

Yard & Garden blog, 2019

This is the Q&A for the Yard and Garden show for July 19, 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: Jay Seaton, District Forester for the Lower Platte South NRD

blossom end rot zucchini
Blossom end rot on a developing zucchini

1. The first question of the show was regarding fruit development on zucchini. The fruits begin to develop and then one end begins to die. What is causing this?

A. This sounds like blossom end rot, it can happen in zucchini, tomatoes, peppers, watermelons, and others. Blossom end rot is when the end of your vegetable that is away from the plant rots and turns black. It occurs on the end of the vegetable that had the flower, hence the name blossom end rot. The cause of this disease is a calcium deficiency, but calcium is in the soil in sufficient quantity, uneven watering will reduce the ability of the plant to access this calcium. Calcium has to be dissolved in water for the plant to be able to obtain it from the soil. Adding calcium to your garden is not effective for managing this problem. Not all of your produce should be affected by this problem, they tend to grow out of these conditions later in the summer, so there is no need to treat your garden for blossom end rot. Maintain moisture and mulch to help with this disorder.

This caller also wondered why his pole beans are not producing yet. He shared the seed with a friend and that friend has harvested but he has not. Why is that?

A. This is likely an environmental issue. Give the plant a little more time to produce the beans. The friend’s garden would have a different microclimate from your garden it may have more sunlight or more heat radiating from a nearby building that your garden doesn’t have.

2. This caller has zucchini that is dying. They seem to have rotten roots when going to look at why they have died. She waters with a hose on trickle twice a week for 30 minutes each time. What is wrong with them?

A. This sounds like too much water is getting applied to the plants. Jay estimated that this was likely applying about 5 gallons of water per week, which is quite excessive. It would be better to use a soaker hose or measure the amount of water applied to the plants each time you let the hose trickle. Vegetable gardens only need about 1 inch of water per week.

3. A caller has pickling cucumbers that are growing good but as they grow one end of the cucumber becomes smaller than the other end. What would cause this?

A. This is likely due to heat stress. There isn’t much we can do to avoid damage from the hot weather. Make sure that the plants are mulched and they are receiving the correct amount of water.

4. This caller has tomato plants with brown leaves at the bottom of the plant. What is causing this?

A. This is likely a fungus. We have seen quite a bit of early blight this year already. Look for concentric rings in the brown spots on the leaves. If it is just a few leaves, pull those leaves off the plant and destroy them. Be sure to keep the plants mulched and water from the base of the plant rather than overhead irrigation to help reduce the spread of the disease.

japanese beetle JAK582
Japanese Beetle, Image from Jim Kalisch, Retired from UNL Entomology

5. What can be done about Japanese beetles? This caller said she was going to try traps and wondered about homemade traps.

A. Don’t use traps, they will attract more Japanese beetles than what you have in your landscape already. Spray all of the areas at the same time. She said one day she would spray the garden, the next a shrub, and the next a tree. If you avoid spraying in areas where they are commonly found, those other locations will become a safe haven for the beetles. Sevin is a good insecticide to use to control the beetles. Be sure to read and follow the label for spraying every 10-14 days and for the PHI, to know when it is safe to harvest again after spraying. Using grub control in the lawn can help. You can also go out in the evening when the beetles are grouped up to knock them into a bucket of soapy water to kill them.

6. This caller wants to know if they should hold back on fertilization of roses and garden now due to the heat?

A. If your plants look fine, don’t worry about fertilizing them right now. Avoid fertilizing the vegetable garden this time of the year. If the nitrogen level is too high around vegetable plants, the plants will grow large and beautiful but will not produce fruit because nitrogen is for leafy growth of the plant. I usually advise avoiding fertilization of the garden this late in the season.

7. The last caller of the day has a sweet potato vine with holes in the leaves. She saw a grasshopper the other day, would that be causing the problem?

A. This could be from grasshoppers, especially since you saw some on the plant. Use Sevin to treat for them. Make sure you spray the grassy ditches and roadsides as well, which is where grasshoppers are found more often.

She also has zucchini plants that have gray, translucent spots on the leaves. What would cause that?

A. She sent a picture to clarify the problem. It looked like a slight fungal disease. It is nothing that is too damaging to the plants. Copper fungicide could be used but I don’t think it is necessary. Good sanitation is key to controlling fungal diseases in the garden. Mulch the garden and avoid overhead irrigation during the season to help prevent splashing spores from the ground and from plant to plant. Remove the plants from the garden at the end of the season.