Yard & Garden: July 31, 2020

This is the Q&A for the Yard and Garden show for July 31, 2020. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am, this is the last summer episode of the year. 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.

* New this year: Join us on September 11 & 18 for fall episodes!

I will put the Q&A from these shows here on the blog as well.

Guest Host: Katie Kreuser, Extension Educator in Cass County

1. The first question of the show was a listener who was wondering if Hops will grow well in Kansas?

A. It should do fine in northern to central Kansas, Katie isn’t sure about the southern part of the state. She said it grows well in the Kansas City area but too far south will not have enough sunlight for it to grow well. Katie also mentioned that to grow hops commercially, you should line up a buyer first because it needs to be used to make beer soon after harvest for best success.

2. How can you control crabgrass now?

A. Now is not the time for crabgrass control, it is too late. At this time of the year, any crabgrass that is growing in the yard will be large and mature. Crabgrass is an annual, weedy grass so it will die with the first frost. In the spring, around late April, use a crabgrass pre-emergence herbicide on the lawn. This could be reapplied in mid June to get season-long control against crabgrass. There are post-emergence herbicides for crabgrass, but will not be very effective on mature plants in August.

3. This caller has roses that are covered with green beetles. What are they and how can they be controlled?

A. These are likely Japanese beetles. You can use sevin or other insecticides. They will likely not kill the roses, but will make it look bad. Most of the damage for this year is likely already done. Look at the tree for more green beetles with copper-colored wings or elytra. If you don’t see many beetles, forego the spraying for this year. You can also use a bucket of soapy water and knock many of the beetles into the bucket to kill them. Go out in the evening when they are grouped up and you can get many at once.

4. A caller who is new to gardening was curious what types of plants can be added to a garden this time of the year? Can he plant tomatoes or cucumbers?

A. A fall garden would be great this time of year. Planting of a fall garden can be done until the middle of August. You can plant the spring, cool-season crops again in the fall and often be more successful than you were in the spring. Things like broccoli, cauliflower, cabbage, Brussels sprouts, carrots, radish, lettuce, and spinach. It is too late in the year for the warm season crops like tomatoes, peppers, or cucumbers. These plants are more sensitive to colder temperatures and wouldn’t have enough time to mature prior to the first frost.

5. This caller has crabgrass in his lawn. He will use a pre-emergence herbicide in the spring to control that. He is wondering, though, when he should overseed the lawn to fill in the bare spots?

A. Late August through mid-September is best. If you are having troubles with weeds in the lawn, you can use a mesotrione product, such as Tenacity, at seeding. This will help reduce the crabgrass and other weeds when trying to get the new turf established.

6. A caller has something that is digging 4-5 inch holes in the yard with no tunnels. What is causing that?

A. This could be from a number of different wildlife animals. It would be best to send pictures to know for sure. I would have to contact a wildlife expert for diagnosis.

7. The final question of the show was from a caller who has a vine coming up in her yard, it is not bindweed. The plant has heart-shaped leaves with dark green leaves and white colored veins. What is it?

A. This is honeyvine milkweed. It can easily be pulled from the garden. Pull it when it is small, before it vines up on other plants. You could also use the ‘Glove of Death’ method. This 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 stem and leaves of the vine to kill it.

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

Yard & Garden: July 24, 2020

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

1. The first question of the show was regarding peppers that are in a garden next to a soybean field. The peppers are wilted now and the caller was wondering if this was from herbicide drift?

A. Herbicide injury doesn’t typically look like wilted plants, that will cause cupped leaves or leaves that are deformed. If the plant is wilting, it could be from root issues. Make sure that the soil is dry before watering again. It could be from too much water.

2. The second caller is also struggling with his pepper plants. They seem to be quite wilted as well. The wilting seems worse during the heat of the day. Could it be something else?

A. With more information, it seems that both pepper plants seem to be having troubles with heat stress, which is common this year, across the listening area. There really isn’t much to do to fix heat stress, water won’t necessarily help with heat stress. Give them time and they will pull through and be fine. Keep them watered, but don’t overwater.

3. A caller has a linden with skeletonized leaves. What is the problem?

A. Japanese beetles are likely causing the problem. You can use sevin or other insecticides. They will likely not kill the tree, but will make it look bad. Most of the damage for this year could be done already. Look at the tree for more green beetles with copper-colored wings or elytra. If you don’t see many beetles, forego the spraying for this year.

4. This caller has bagworms on her cedars in the pasture. Will those move to her windbreak trees this year?

A. They should be in their location for the year now. They typically only move around when they are very small, at this point in the year they shouldn’t move much.

5. When is a good time to cut peonies back?

A. The fall is the best time to cut peonies and clean the plants up. They will turn brown in late September to early October, that is when they should be pruned back. This allows the plants to build sugars all summer to help with early spring bloom next year.

6. The final question of the show was from a caller that has a weedy tree in her yard that looks like a palm tree. What could that be?

A. Without seeing the tree it is hard to tell for sure what it is. It could possibly be a tree of heaven or a pokeweed plant. It was advised that she send a picture to the Extension Office.

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

Yard & Garden: July 17, 2020

This is the Q&A for the Yard and Garden show for July 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: Sarah Browning, Lancaster County Extension Educator

2015-07-17 10.51.40
Green June Beetles

1. The first question of the show was from a listener who brought green beetles into the studio for identification. These were found in his trees and he wants to know what they are and how they should be controlled?

A. The beetles were Green June Bugs. These are a native insect species that can be found on many different plants. They can be ravenous feeders in grapes and occasional feeders in vegetable gardens, but on trees they are not very damaging. If they feed on vegetable gardens or grapes, you can use sevin or eight on them.

2. This caller has a Linden tree that is 12 years old that is losing leaves now. The leaves turn brown as well. They did recently give it a deep watering, but that isn’t seeming to help. What is wrong with the tree?

A. Check the tree thoroughly for Japanese Beetles, it is one of their favorite plants to feed on. They will feed heavily causing the leaves to look like lace and then the leaves will turn brown. The trees can look fully brown by late summer. If it is, you would want to work with an arborist to spray the tree. Be very careful with what you spray lindens with and when you spray them to not harm pollinators. If the leaves don’t have holes in them, it could be from a stem girdling root which cannot really be fixed so late in life.

3. A caller has peppers that have white spots on them. What caused this?

A. This is likely due to drift from Roundup or another glyphosate product. Wind can drift the particles which will leave white, irregularly shaped spots randomly across the leaves. If it was from a disease it would be more tan or brown in color.

4. This caller has tomato plants that are loaded with green tomatoes that are not turning red. What is disrupting the maturation process of the vegetables?

A. When the temperatures are so hot, as they have been, the fruit ripening process is slowed down or stopped completely. They will mature when the temperatures break to cooler temperatures.

5. A caller wants to know when she can harvest wild flower seeds to reseed in a new area in  her landscape?

A. The seed needs to fully mature while still on the parent plant. Make sure the seed head is dried and brown, then you can cut off the stalk and move the seed to the new location. If you can easily shred the seed  head with your fingers, the seed is mature and can be reseeded in a new location.

6. This caller has tomatoes and beans with troubles in the garden. The tomatoes have brown leaves on the bottom of the plant, what is causing that? The beans have flowers on them but no fruit has been set, why are they not producing beans for harvest?

A. The tomatoes likely have early blight, it is a common fungal disease that we are seeing this year. You can just remove the infected leaves and discard them to reduce the disease. If the plants still have troubles, you can spray them with a copper fungicide if necessary.

As for the beans, the heat is likely delaying fruit set. In temperatures this hot, the flowers can develop but the pollen can be killed so fruit will not set. Give the plants a little more time and they will start producing beans once the temperatures cool off.

7. A caller has columbines that are in a garden bed overrun by weeds. She wants to redo the bed to help get rid of the weeds. When is the best time to dig them up and do some work then replant them?

A. The fall or spring would be a good time to dig up, divide, move, and redo the garden space. When the temperatures are cooler. When we move or divide plants we break their root system, making it harder for the plants to get the needed moisture to survive. It is best to do these things when it is cooler so the drought stress isn’t as high.

8. This caller has tiger lillies that were knocked over by the wind and broken. Can the seed be moved to another location?

A. Make sure that the seed matures on the plant. If the stems were broken so the plant is not still maintaining the seed, they may not be able to be reseeded to a new location because the seed wouldn’t be mature. If that is the case,  you can divide the plants and plant some in the new location. September would be a good time to do this.

9. Is there any post-emergence herbicide that can be used in an asparagus patch that won’t hurt the asparagus?

A. No, there isn’t anything for post-emergence. You can use preen that is labeled for use in the asparagus in the spring prior to germination of the annual weed seed and again in the middle of the summer. This will help with annual weeds. For perennial weeds you can use roundup or another glyphosate product early in the spring prior to emergence of the asparagus. You can also use it after the final harvest of the year. Cut out all of the stems of asparagus and pull mulch or the soil up over the stems so no green is showing, then spray the roundup over the bed to kill the weeds and not harm the asparagus.

10. This caller has an old lilac that has leaves that look bad. Can it be cut down now?

A. It can be cut back with a rejuvenation cutting in September. This is when the lilac is cut back to 6-8 inches above ground. This will help to rejuvenate the plant to newer, healthier growth. This method will disrupt the flowering for a year or two, but it will eventually flower again. The lilac can also be caned out every year by removing 1/3 of the largest, least productive canes every year to remove those canes that are not improving the health of the plant.

11. A caller asked why his tomatoes look good but have no fruits or flowers at this point? It was hit by herbicide drift a month ago, but they have grown out of that.

A. The heat is pushing back maturation of the fruits right now. However, if your plants have no fruits at all, the herbicide injury could have stunted the plants. The combination is pushing back maturation of the fruits. Eventually they will flower and produce fruits, just give it time.

12. The last caller of the day asked about green beans that are blooming but have no fruits. What is causing this?

A. The heat is likely delaying fruit set. In temperatures this hot, the flowers can develop but the pollen can be killed so fruit will not set. Give the plants a little more time and they will start producing beans once the temperatures cool off.

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

Yard & Garden: July 10, 2020

This is the Q&A for the Yard and Garden show for July 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: Justin Evertson, Green Infrastructure Coordinator for the Nebraska Forest Service

1. The first question of the show was from a caller who has a 20 foot tall blue spruce that the top 5-6 feet is turning brown. What caused this and what can be done about it?

A. This is likely from a canker. Canker fungi are common in blue spruce trees and will often cause the top portion of the tree to die. The dead area should be cut out but then you will lose the apical dominance and the tree won’t grow upward much after removing the terminal bud. It will die back to a certain spot then stop, the rest of the tree will remain healthy.

2. This caller has tomatoes with leaves that are curling. What is causing this?

A. Unfortunately, we aren’t completely sure what is causing this damage, but it is widespread throughout the whole state this year. It could be from herbicide damage due to chemicals still being used later in the year with the cooler spring and sudden change of temperatures to very hot. There is also thought that it could be from the beet curly top virus. This could also be from watering issues such as over watering or underwatering. It would be best to just pull the plants out because if it is the virus it can spread to the other plants and if it is herbicide injury the produce would not be safe to consume. If the other plants look ok, this would be the best option.

3. A walk-in listener has an row of arborvitae that have developed brown spots in them this summer. What is causing this?

A. Arborvitae struggle with the extreme temperatures that Nebraska have. The damage looks mostly like environmental stress. Keep them sufficiently watered, but don’t overwater. Keep them mulched in. Depending on the amount of dieback, they may survive.

4. This caller planted broccoli in mid to late May, now the leaves are developing holes and there is no head developing yet. What is wrong with it?

A. It is likely that the broccoli was planted too late and may not develop the head. Broccoli is more of a cool season plant, they don’t grow well in this heat. The holes are likely due to one of the looper caterpillars that are common on broccoli. Sevin will help with that.

5. A caller has a large pine tree that is looking dead, quite suddenly. It is losing a lot of needles and has turned brown. What is wrong with it?

A. This is likely due to pine wilt disease. There is no cure for the disease and no way to prevent it prior to infection. The tree should be removed.

She also wondered if she could still spray for bagworms?

A. We are quickly nearing the end of the time frame for spraying for bagworms. They are best sprayed when the bags are 1/2 inch in length or less. As the bags get too big, the sprays become less effective. Spraying soon should be ok, but if you wait too long you may not see 100% coverage from the sprays. Use Tempo and spray in the next week for best control.

6. This caller has an apple tree that didn’t bloom this year and the leaves look bad. Will it survive and is there anything to do for the tree?

A. The frost likely injured the blooms. They will not produce apples this year if that is what happened. The plants will still survive. After discussion, it seems that the apple trees have rust on them, which is common. The spray time has passed. You can spray the trees next spring with a copper fungicide for the rust or use an orchard fruit tree spray through the season next year to work on insects and diseases in the trees.

7. A caller has a forsythia and a red twig dogwood that have grown too large for the area. When can they be pruned so they aren’t blocking windows?

A. If flowers are not critical, these plants can be pruned most anytime. Pruning right now would reduce the flowers for next year, since they are mostly set on for next year already. However, the best time for pruning the forsythia is just after it has finished blooming and the dogwood would be in the late winter. They can both be rejuvenated by pruning all the way back to the ground, about 6-8 inches above ground. The rejuvenation pruning should be done in the fall.

8. This caller has tomatoes and cucumbers with spots on the leaves. Is this a fungus and should a fungicide be used?

A. This could be from a fungus, it is hard to tell without seeing the plants. However, it is not the same fungus, these would have different types of fungi. Fungi are typically host specific. If there are just a few leaves that are damaged, those could be removed and destroyed. If the plant seems to have a lot of damaged leaves, a fungicide could be used if desired. Watering from below on the plants or earlier in the day if using overhead irrigation can help reduce the spread and incidence of the disease. If using a fungicide, be sure to read and follow the label and follow the PHI or pre-harvest interval. The PHI is how many days to wait for harvest after an application of a pesticide is made.

9. A caller has 3 river birches and a corkscrew weeping willow. After the late frost this spring, there are branches that are now dead, with no leaves. Will these plants survive?

A. It is unlikely that they will survive if they are not green now. It is likely that the late frost injured them and they cannot recover. If it is a few select branches, you might be able to remove them and the tree may be ok, but if the majority of the canopy has no green leaves on it, they will not survive. These plants can struggle with the extreme temperatures of Nebraska.

japanese beetle JAK582
Japanese Beetle, Photo from Jim Kalisch, UNL Entomologist Emeritus

10. What can be done about Japanese Beetles?

A. The plants that the Japanese beetles are found on can be sprayed with carbaryl, bifenthrin, or chlorantraniliprole. For organic options neem or pyola can be used. Don’t use the traps, they will bring in more beetles than what you already have. Grub controls can help a little with the population size. Be sure to avoid spraying the flowers of any plants.

11. This caller has a wild plum thicket along their driveway. It is spreading too much into the driveway. When can it be pruned back to avoid scratching cars that drive by?

A. The areas of the plum thicket that are creeping out of normal growth can be cut back most anytime. They are a tough plant and should be fine.

She also has a vegetable garden that is not growing well this year. It is the same location that she has gardened for years, but the plants just are not doing well. Can she add manure to it and if so, when?

A. You can add manure to the garden. For food safety guidelines, fresh manure should be applied 120 days prior to harvest of any crops, so we advise adding manure in the fall. However, since this has been a good garden space, I would suggest doing a soil test prior to soil amendments to know exactly what the problem is and know how to fix it.

12. A caller has a silver maple that lost limbs and has started to split from the recent storms. Can the tree be pulled back together with a cable?

A. It is best to work with an arborist on this, to ensure it is done correctly. However, the tree may be too large for a cable to effectively help with the split. It may be time to remove this tree. Silver maples are prone to decay from wounds such as this, it is likely the beginning of the end for the tree anyway.

13. The final question of the day is about a black hills spruce that is browning sporadically on the ends of branches throughout the tree. What is wrong with it?

A. This tree could have freeze damage on the tips of the branches from the late frost and snow this spring. It could also be from a disease called sirococcus or needle cast. It would be too late for treatment with either of these diseases, but they shouldn’t kill the tree. The brown areas can be pruned out and next spring, it might be good to spray the tree with a fungicide.

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

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 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 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.

Yard and Garden: July 12, 2019

Yard & Garden blog, 2019

This is the Q&A for the Yard and Garden show for July 12, 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: Sarah Browning, Extension Educator in Lancaster County

1. The first question of the show was about ivy growing on a garage. The caller had Japanese beetles earlier this year and sprayed with sevin. Now he is seeing a lot of flying insects, one looks like a lightning bug. What type of insect would this be and will they cause damage to his ivy?

A. They could be lightning bugs which will not harm your plants. Japanese beetles will come back, it would be best to keep spraying to ensure they stay away. You can use the sevin every 10-14 days or you can use a product containing Azadirachtin which has some repellent properties so it will help to keep the Japanese Beetles away longer.

2. A caller has a newly planted maple tree that has brown spots on the leaves. It looks like something is eating it but she can’t find any bugs. The spots look like brown strips with yellow around it. What is causing that?

A. This could be the tree drying up and getting heat stress. This tree was just planted this year so it isn’t established well and will dry out faster in this heat. She has been watering by hand and that isn’t getting the tree enough water. It would be better if she watered with a small sprinkler for about 45 minutes once a week.

3. This caller has a 40-year-old Ponderosa Pine that had diplodia tip blight that got so bad she removed the tree. There is a blue spruce nearby, would that tree be getting the tip blight as well? The spruce has tips of the branches that are bent over and the needles are all bunched together. What would cause that?

A. Diplodia tip blight will not affect spruces. It is a problem for pines, mostly Austrian and Ponderosa. This is not what is affecting the spruce. The damage on the spruce sounds like sirococcus shoot blight. It is past the treatment time for this disease, but it won’t kill your tree in one season. In the spring spruces can be sprayed with chlorothalonil when the shoots are 1/2-2 inches in length and repeated every 3-4 weeks if frequent rains occur.

Blossom end rot on tomato
Blossom end rot on a tomato

4. What can be done for blossom end rot in tomatoes?

A.  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.

5. A caller wants to know what to plant for a fall garden and when it should be planted.

A. Fall gardens can be very beneficial and work better than spring gardens due to the cooler temperatures and higher amounts of moisture in the fall. Start transplants indoors now for things like Brussels sprouts, broccoli, cabbage, and cauliflower. The average first frost date for most of Southeast Nebraska is October 6-16, this comes from data from the High Plains Regional Climate Center. You can use the first frost date to figure out when to plant fall crops. Use the first frost date as a starting point, count backward the number of days to harvest listed on the packet of seeds and add a 10 day fall factor because the plants will mature slower due to the cooler weather. Plants or seeds should be planted in late July to early August. You can also plant your second crop of warm season vegetables now if you haven’t yet to get a longer harvest period and possibly avoid problems with insects and diseases during their peak time.

6. This caller has a rose bush with something eating the leaves off it. What would cause this and how can it be controlled?

A. This could be from a couple of different issues. Japanese beetles will feed on the leaves of roses and cause the leaf to look like lace with little leaf left besides the veins. Rose slugs can do some damage to roses but it looks worse than it is and the feeding should be nearing completion for the year. If you aren’t seeing the insects, it could be rose chafers that feed at night. It could also be from a disease such as black spot. Look for a product that contains an insecticide and fungicide to help with any of these problems. A liquid would be better than a dust.

7. A caller has brown spots in his lawn. What is the problem and how can he fix it?

A. This could be due to either brown spot or dollar spot. These two diseases are quite common this year due to the wet spring and early summer conditions we faced. In a home lawn it isn’t usually necessary to use a fungicides because the fungi don’t kill the lawn and they are sporadic from year to year. It will fade soon and the grass will green back up. These diseases don’t affect the crown of the grass plant so it will easily grow out of it after a few mowings. Through discussion, we learned that his underground sprinkler system waters the lawn from 1am-6am. It was suggested that he do an irrigation audit and move the time for watering forward to 4am-10am. Watering overnight keeps the lawn wet in the cooler, dark environment which is great for disease development.

8. The final caller of the show have sugar maples that leafed out well this year but now the leaves are turning brown and dropping off the tree. What is causing that?

A. This could be from anthracnose, a fungal disease of the tree. It can infect the leaves and cause them to fall from the tree. It could also be from not watering enough now that the rains have reduced or from scorch. Be sure to water the tree and look for damage on the trunk or girdling roots. Look for borer holes as well and treat with imidacloprid if holes are present. It is most likely from an environmental condition, which we cannot change. The tree should be fine.

Attack of the Beetles

JB Damage
Damage from Japanese Beetles

This year, like always, we are facing insect issues in our lawns and gardens. It is important to remember that not all insects are bad, in fact the majority of all insects are beneficial in some way. However, when they are found in large populations or damage our plants, or both, we get concerned.

 

Soldier Beetles

Soldier Beetle
Soldier Beetle, Photo from Soni Cochran, Lancaster County Extension Assistant

Soldier beetles are common this year. These are the yellow beetles found in large quantities throughout the area this year. They are often confused with fireflies because they are both beetles without hardened elytra, like many other beetles, and they are similar in appearance. The soldier beetle we are seeing is golden in color with a black spot on each wing on the back. They are commonly found around Linden trees as well as many other flowers. There is no need to control soldier beetles because they are great pollinators and will not harm our plants or us.

Japanese Beetles

Japanese Beetle, 7-16 Acreage
Japanese beetle adult on the left side and grub on the right side, photos from Jim Kalisch, UNL Entomology

Japanese beetles have been more of a problem for southeast Nebraska over the past couple of years than they had been in the past. This is an invasive insect from Japan. Japanese beetles are problematic insects as both larvae and adults. The larvae are a type of white grub which feed on the roots of our grass, causing large brown dead spots in the turf that are easily lifted up like a rug from the floor.

Adult Japanese beetles are 7/16 inch-long, metallic green beetles. The elytra, or wing coverings, are copper. As adults, Japanese beetles feed on over 300 species of plants including trees, shrubs, fruits, vegetables, field crops, weeds, and other ornamental plant species. Some of their favorite food plants are roses, lindens, and grapes. Adult beetles feed on the foliage, flowers, and fruits of these plants. They feed on the upper surface of the leaves and cause a skeletonized pattern to the leaf where the veins of the leaf are often left behind but the rest of the leaf is chewed away. In some cases, they will consume the entire leaf. This can stress the plants, and in high populations of beetles can even kill the plant.

Grubs can be controlled with chlorantraniliprole or imidacloprid in June. Adults can be controlled with systemic insecticides such as imidacloprid or dinotefuron around Mother’s Day to give the products time to get throughout the trees and shrubs being treated. Currently, no systemic insecticides can be used on Lindens though, due to the damage to pollinators. Tempo and Bayer Advanced Lawn & Garden Multi-Insect Killer (cyfluthrin), Ortho Bug B Gone (bifenthrin), or Sevin (carbaryl) would be a few other options that can be used on Lindens and others. These options will only work for about 2 weeks so they may need to be reapplied.

Blister Beetles

blister beetles, K. Jarvi
Black and gray blister beetles, Photos by Keith Jarvi, Emeritus Extension Educator

Blister beetles were a real problem in our vegetable gardens last year, and they are back. Blister beetles are ½ inch long, powdery gray colored beetles with black antennae. They can feed on our tomato plants as well as some other vegetable crops. They can damage our plants, but they are also beneficial because they feed on grasshopper eggs. If you find them in your garden, you can treat with general insecticides such as sevin or eight. Be careful handling these beetles, some people develop blisters after handling them.

What’s that green beetle…

Green Beetles Blog post

All plants are wonderful. However, it is highly unlikely to find a plant that has absolutely no insect problems. This year we have been seeing a couple of unusual beetles wreaking havoc in our vegetable gardens and they can be found on our trees and shrubs as well. Japanese Beetles and Green June Beetles have been more problematic in southeastern Nebraska this year than most other years.

Japanese beetles are an invasive insect from Japan, where it is not a major pest due to the natural predators found there. This pest was first found in the United States in a New Jersey nursery in 1916 and was likely introduced in infested iris bulbs from Japan.  Since this initial introduction, Japanese beetle populations have steadily expanded westward.

Japanese beetles are problematic insects as both larvae and adults. The larvae are one of the four most common types of white grubs found in Nebraska. As a white grub, larvae feed on the roots of our grass, causing large brown dead spots in the turf that are easily lifted up like a rug from the floor. Adult Japanese beetles are 7/16 inch-long, metallic green beetles. The elytra, or wing coverings, are copper. These beetles can be distinguished from similar looking beetles by the six tufts of white hair along both sides of the abdomen. As adults, Japanese beetles feed on over 300 species of plants including trees, shrubs, fruits, vegetables, field crops, weeds, and other ornamental plant species. Some of their favorite food plants are roses, lindens, and grapes amongst others. Adult beetles feed on the foliage, flowers, and fruits of these plants. They feed on the upper surface of the leaves and cause a skeletonized pattern to the leaf where the veins of the leaf are often left behind but the rest of the leaf is chewed away. In some cases, they will consume the entire leaf. This can stress the plants, and in high populations of beetles can even kill the plant.

Green June Bug vs JB

Green June beetles are often being found this year as opposed to other years. They are very large, usually more than one-inch in length. They are dull green with some brownish coloration to the elytra and a tan border along the margins of their elytra, which are the hard wing coverings on a beetle. Green June Beetles will feed on ripe fruits and vegetables like tomatoes, corn, and grapes. They will feed on the fruits and the leaves of the plants and as an immature, they are also a white grub species.

These 2 green beetles can be controlled through multiple methods. As larvae, they are best controlled with insecticides applied to the lawn in the months of May, June, and July. There are many different options available including the most common grub control, Merit which contains imidacloprid. Pesticides can be used on the adults in plants, however, be sure to avoid use of pesticides directly on the flowers of these plants to avoid harming pollinators. Imidacloprid, sevin, eight, or other general insecticides can be used on trees and shrubs to control the beetles. In low adult populations, you can hand pick the beetles off of plants and throw them into a bucket of soapy water to kill them and not harm any pollinators.