Bob Morris is a horticulture expert living in Las Vegas and professor emeritus for the University of Nevada. Visit his blog at xtremehorticulture.blogspot.com. Send questions to Extremehort@aol.com.
Q: Two years ago I planted Thompson seedless grapes. The first two years there were no grapes, and I did not expect any fruit. This year, there are leaves and no fruit. They were pruned the same way as my red seedless grapes, which were very prolific. Is there something special that I must do to make the vine produce?
Q: This year has been the worst for weeds and grass coming up through the rocks. I’ve tried Bayer Advanced all-in-one concentrate that acted like a fertilizer and strengthened their growth. I got Roundup weed and grass killer concentrate. Two weeks later and the grass is coming up like I planted it. What do you suggest I use to spray on this grass to kill it?
Q: Could you provide me with a copy of the mulch trial you conducted on fruit trees several years ago? You randomly applied mulch to different fruit trees and grew some without mulch and had some remarkable results.
Q: During the first year with my apricot tree, I sprayed it with soapy water to control aphids. Every day I check the leaves, but the apids never stop. Is this good a spray to use?
Q: I was reading up on controlling the leaf-footed plant bugs on my pistachio and almond trees and came across a recommendation by the University of California to use a pesticide containing bifenthrin. I see some Ortho products for lawn and garden contain bifenthrin. Is this a pyrethrin or something similar like you are recommending? Could this be used to spray the almond and pistachio every two to three weeks until it gets hot?
Let’s talk about wind damage. If you didn’t sustain wind damage to your landscape, you are extremely lucky. It was fortunate these high winds occurred early in the season, and many trees were not yet full of leaves. If it had been a few weeks later, the damage would have been worse.
Q: I’m curious if there is any reason other than drought or overwatering that would cause my donut peach growing in a container to wilt within 24 hours? I pruned the dead branches off and touched very little of the live wood.
Q: How close do I need to plant a pollinator tree? I want to plant more fruit trees and was curious how close it needs to be? My neighbors have various fruit trees, and I am about a half mile from Gilcrease Orchard. Is this close enough to be effective, or should I plant my own?
Aphids are on fruit trees, roses, winter vegetables and other landscape plants. They love cool nights but warm daytime temperatures for feeding and breeding. Their feeding causes new leaves to curl on the edges and glistening, sugary sap on leaves.
Q: My husband and I just moved to Summerlin, and I am seeing pink and white blooms on trees in this area. Do you know what kind of trees these are?
Q: Is it too late to fertilize my nectarine tree with buds starting to form? Fertilizer instructions advise to apply it in early February before buds appear.
Q: All the large pines on my property have branches that are turning brown in some form or another.
Right now is the time to prune grapes. Prune citrus now if there has been damage from cold weather. If your citrus is young, prune it to tree form, removing side shoots to about the height of your knees. I delay pruning citrus and grapes until I am sure most of the cold weather has passed, which is mid- to late February.
Q: Recently you recommended applying compost to lawns. I am confused if you mean steer manure. How often do you recommend doing this? When should I do my first application? My lawn is approximately 1,000 square feet. How much compost should I buy?
Q: We have seven large olive trees on our property. In the past, we used two different local tree services to spray our trees to minimize the amount of olive production. One company told us we needed two applications in early spring, and the other said we only needed one. Both came at a very high cost, and the results left much to be desired. Every day we had to sweep up hundreds of olives. Do you have any suggestions as to what might work and the timing of when the trees should be sprayed?
