Yard and Garden: July 20, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for July 20, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: John Porter, Urban Agriculture Program Coordinator for UNL Extension and Nebraska College of Technical Agriculture (NCTA)

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

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

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

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

Harlequin Bug, Alton N Sparks, Jr, Univ of GA, Bugwood

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

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

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

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

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

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

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

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

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

Bagworm4

Bagworm

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

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

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Yard and Garden: June 29, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for June 29, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Roch Gaussoin, Extension Specialist from UNL

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

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

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

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

This listener also wondered if his lawn should be mowed?

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

2018-06-29 11.05.53

Purslane

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

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

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

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

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

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

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

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

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

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

Yard and Garden: June 22, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for June 22, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Kathleen Cue, Dodge County Extension Educator

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

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

2. When is the best time to move asparagus?

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

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

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

Yellow Nutsedge-Howard F. Schwartz, Co. State Univ, Bugwood

Nutsedge photo by Howard F. Schwartz, Colorado State University, Bugwood.org

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

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

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

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

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

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

Bagworm4

Bagworm

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

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

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

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

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

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

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

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

11. Is it too late to prune lilacs?

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

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

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

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

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

Yard and Garden: May 11, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for May 11, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Dr. Paul Read, Professor of Viticulture, UNL

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

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

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

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

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

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

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

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

blossom end rot zucchini

Blossom End Rot on Zucchini

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Yard and Garden: April 13, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for April 13, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Kyle Broderick, Coordinator of the Plant & Pest Diagnostic Clinic at UNL

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

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

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

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

2. How do you kill grass growing in peony plants

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

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

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

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

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

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

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

Ant mounds from YandG listener

Larger Yellow Ant Mounds

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

Yard and Garden: April 6, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for April 6, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Hosts: Jonathan Larson, Douglas/Sarpy County Extension Educator in Entomology and Jody Green, Lancaster County Extension Educator in Entomology

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

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

2. What is the correct mowing height?

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

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

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

Termites

Termites, Photo from the University of Nebraska Department of Entomology

4. Does wood mulch attract termites?

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

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

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

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

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

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

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

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

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

Yard and Garden: March 30, 2018

Y&G Blog Photo, 2018

This is the Q&A for the Yard and Garden show for March 30, 2018. Yard and Garden Live is a call-in radio show I do on KUTT 99.5 FM from 10-11:30 am and it will run through August 3, 2018. It can also be found on kutt995.com for online listening. If you missed a show or just want to read through the questions, I have written them all in my blog and will continue to do so throughout the season.

Guest Host: Justin Evertson, Green Infrastructure Coordinator, Nebraska Forest Service

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

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

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

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

3. When should a person fertilize their lawn?

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

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

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

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

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

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

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

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

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

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

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

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

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

What to do in the Spring?

Spring Things Blog Post

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

Henbit

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

henbit, steve dewey, Utah State Univ, Bugwood

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

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

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

Lawncare

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

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

Asparagus

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

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

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

Yard and Garden: June 2, 2017

Yard & Garden for blog, 2017

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

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

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

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

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

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

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

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

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

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

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

Forsythia-Richard Elzey, Flickr

Forsythia, Flickr image courtesy of Richard Elzey per CC license

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

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

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

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

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

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

8. How do you transplant a wild rose?

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

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

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

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

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

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

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

12. How do you control weeds in asparagus?

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

Carpenter Bee, J. Kalisch

Carpenter Bee photo from Jim Kalisch, UNL Entomology

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

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

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

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

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

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

Yard and Garden: May 12, 2017

Yard & Garden for blog, 2017

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

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

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

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

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

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

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

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

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

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

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

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

Tree hole for blog

Photo of the damage occurring to the Maple tree.

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

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

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

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

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

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

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

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

Summer Patch, L. Giesler turf update

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

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

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

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

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

11. When is the best time to start asparagus?

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

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

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