This is the Q&A for the Yard and Garden show for May 10, 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 Hosts: Kevin Christiansen, Horticulture Instructor at SCC Beatrice & Chelsea Tietjen, Agronomy and Entomology Instructor at SCC Beatrice
1. The first caller of the show wants to know when to start spraying his apple trees with the orchard fruit tree spray? He also wants to know if it is too hot here to grow cabbage because it is hard to get a harvest?
A. Orchard fruit tree sprays will combat both insect and disease problems on fruit trees. Sprays should begin as soon as pink is seen in the buds, but should cease during blooming. Since this caller hasn’t begun spraying yet, it would be fine to just start as the blossoms are falling off the tree. You want to allow the pollinators to come to the tree without harming them, so no sprays should be done while the trees are blooming. This spray should be applied every 10-14 days through the growing season, up until harvest.
As for the cabbage, it should be fine growing here, but some years it can get hot quickly and that can cause our cool season crops to bolt. Cabbage may be better grown in the fall due to the quick warm up in spring that usually happens here in Nebraska. For more information on growing cabbage, visit this article from Lancaster County Extension.
2. This caller was wondering if we would see bagworms later this year than most years due to the colder weather? He also wondered what is the best control for them and when to control them?
A. It is likely that we will see bagworms a little later this year due to the cooler spring we have had. They will hatch at different times in the year because their hatch is weather dependent. Starting in late May, check weekly for the small bags to begin to show up on the trees. When the small bags show up and until they are up to 1/2 inch in length you can spray. Tempo or Bt would be best for control.
3. A caller has lilacs that were planted 2 years ago. They were a small cutting at 1 inch tall when they were planted and now they are only 4-6 inches tall. What fertilizer can he use to get these to grow faster?
A. Mulch would be a better option for these plants since they are so small. This would protect them from weed competition and from accidentally being mowed over and would do much more for the plants than fertilizer would. It would also be a good idea to put a fence up around them to prevent rabbits from chewing them off since they are so small.
4. This caller has cedar-apple rust that is showing up on his cedars. He has sprayed his apple trees, but does he also need to remove the galls from the cedars?
A. The galls will not hurt the cedars and as long as you sprayed the apple trees, that should be sufficient. Pulling the galls off won’t stop the disease for future years because the spores can spread up to 2 miles so they will come from other cedar trees.
5. A caller has a rhubarb plant that is flowering and not producing the stalks for consumption. What can be done to improve stalk production?
A. Cut the flower stalks off at the bottom of the stalk. These flower stalks take energy from the plant. The energy is moved from the leaf production to flower production. The abnormal weather this spring has caused rhubarb to flower more this year than other years.
6. When do you prune snowball bush and lilacs?
A. After they complete blooming this spring, remove 1/3 of the stems at the base of the plant. Remove the largest, least productive canes and leave the smaller, younger, more productive canes.
This caller also wondered what do do for the purple flowering weeds and dandelions in the yard?
A. The purple flowering weeds are henbit. They are a winter annual and will soon die when the temperatures warm up, likely in the next week or so. There is no reason to spray them now. Dandelions are best controlled in the fall with an application of a 2,4-D product. Spray them in the middle of September and the middle of October. The later application in the fall will also help kill henbit as it emerges in the fall to reduce the population for next year.
7. A caller is building a raised bed in his landscape. Does he need to put rock at the bottom to help with drainage?
A. No, it wouldn’t be necessary to add rock to the bottom of a raised bed to help with drainage. Raised beds are built up on the sides with an open bottom. That will be drainage enough for them. Be sure to use good quality soil and some compost, don’t use soil from your yard.
8. How do you control buckbrush in the pasture?
A. According to the Guide to Weed Management from Nebraska Extension, 2,4-D will work on buckbrush in the pasture. For more information visit this cropwatch article.
9. This caller has lillies that are not growing well. The daylilies are short and blooming but they are not growing big at all. Other plants in the bed are fine and these daylilies in other locations are growing larger. What is causing the problem?
A. This may be a soil issue. It might be good to do a soil test. It could also be that the soil is compacted more in that location that are constricting the roots and limiting growth. Add some compost to the soil and work it in around the plants to try to reduce the compaction. A general fertilizer could be tried as well. It also could be that the plants are maybe planted a little too deep. It might be helpful to dig up the plants, add compost or manure to the soil, and replant the daylilies a little higher in the soil profile.
10. The last caller of the day had 2 questions. She is rejuvenating her landscape beds, should she use landscape fabric in them? Also, she has a trumpet vine growing on a trellis that has a lot of dead branching in it, what can she do to remove the dead growth and rejuvenate these vines?
A. Landscape fabric is not necessary in the beds. Landscape fabric can restrict the movement of moisture into the soil and harm the plants. Also, soil and weeds can move in on top of the fabric which defeats the purpose of using it. Finally, if you ever want to change that bed in the future, the landscape fabric is very difficult to remove.
As for the trumpet vine, it can be cut back heavily, but it would be best done early next spring rather than now because it is getting a little late this year. Remove the old, unproductive growth and leave the smaller, healthier growth.