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.
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.