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.
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.