Gardening columnist Tim Daly answers the following questions from readers:
Question: My azaleas and big-leaf hydrangeas need pruning. Is now a good time to prune them? Should I wait until the fall or winter? — Ray, Grayson
Answer: Ray, shrubs such as azaleas, big-leaf hydrangeas, gardenias, forsythia, and other spring and early summer blooming plants produce their buds in the summer months. Now would be an excellent time to prune these plants.
They have not formed the buds for the flowers next year; however, they do so before mid-August. Other plants produce their flower buds on the new growth in the spring and summer and can be pruned during the winter months. Examples include crape myrtles and most roses.
Q: I have several squash plants that have wilted while others are fine. On the bottom of the main stem of the suffering, they are soft, mushy, and some ‘sawdust’ material is present. What could be the cause of this problem, and what can be done to stop it? — Mary, Norcross.
A: Mary, squash vine borers are the cause of the decline of the plants. They are the larvae or caterpillar of a clearwing moth that lays its eggs on the main vine, then the borers hatch and tunnel into the plant. Once that happens, no chemicals will control it.
You may have some luck by using an Exacto-knife or razor blade to cut into the vine. When you see the borer, which will be slightly less than an inch, pull it out. Then cover the vine with soil. The plant may recover. As a preventive measure, you can also bury the vine in the soil and use insecticides such as Dipel, which contains bacteria that target caterpillar pests, Liquid Sevin, or other ones along the main vine early in the season. Please follow all label directions when using pesticides.
Q: I have a couple of peach trees in my backyard. They were loaded with peaches, but suddenly many of them dropped off the plant. What could cause them to shed the fruit? How can I prevent it from happening? — Roy, Buford.
A. Roy, peaches are notorious for producing more fruit than the tree itself can support. Thus, prune peaches yearly, or they will ‘set’ too much fruit, which then will abort or drop when the temperatures get hot during early summer.
Prune peaches in February by removing one-third of the growth to prevent or reduce peach drop from occurring later in the year. Also, when the peaches form on the tree in the spring, they start thinning the fruit, which is removing the small fruit on the branches to where you have only one every six to eight inches.