When to apply disease and pest control products
Q
Is it too early to put a three-in-one insect, disease and pest control product on my Knockout roses? They have the beginnings of some new growth at this time.
A
I do not think we should start using pesticides just yet on our roses — the three-in-one products also contain fertilizer, and we sure don’t need to speed things up. A lot of people have been questioning whether or not they should still prune roses this year, since many have started growing. I recommend pruning all roses with the exception of climbing roses, which should be pruned after the first flowering. Late-season pruning doesn’t hurt the roses, but the later you wait, the later they will start flowering. If you don’t prune, you won’t have as many flowers, and your plants may be huge. Wait until mid-March to early April before using pesticides on roses.
Q
I have several pink surprise lilies in my flower bed. Four years ago, there was plenty of foliage in the spring that died back and many, many blooms in late summer. However, each year since, there has been plenty of foliage, but only one or two blooms. Is there anything I can do to make sure they bloom this year? The foliage is already up.
A
Everything is ahead of schedule this spring. My foliage is fully up on the pink surprise lilies people call naked ladies. You could lightly fertilize your surprise lilies in mid-March. The variety with the pink blooms is Lycoris squamigera. They produce foliage in the spring, which grows for about two months and then dies back. The light pink, naked stems come up about two months later. The red spidery type are Lycoris radiata, and the foliage on those comes up right after they bloom in the fall. It lasts all winter, dying down in the late spring. While the foliage is up on either of these varieties, they are manufacturing the food to produce the flowers.
Q
I read your article on the scale problem in the Little Rock area. I have a heavy infestation on my crape myrtles and my privet bushes. I tried to wash the scale and the mold off with soapy water. It was very difficult and slow going. I then used my electric pressure washer (1600 psi), and it cleaned the trunks and branches in no time and it was much easier. The bark seems very clean with no sign of damage. Next, weather permitting, I will treat with dormant oil and then the systemic insecticide.
A
Great idea, just make sure when using the pressure washer that the stream is not so intense it damages the trunks.
Q
Attached is a picture of one of my hybrid rosebushes. I bought it in North Carolina four years ago. While in the pot, it produced a few white, long-stemmed roses. Once planted in the ground, the bush sent out two different types of stems; one produces small red blooms once a season. The other side has leaves but does not bloom. Apparently, the hybrid rootball has separated. The leaves on each side are quite different. The bloomless side has a barklike growth as shown in the picture. I have cut this side to the ground twice. It regrows again, and by midseason the bark reappears. Do you know what causes this bark to grow? How do I stop it? Although I am not a big fan of roses, the red side is very nice when in bloom, and I would like to continue to have it in my garden.
A
I think you have a few things going on. First, I think your white rosebush was grafted on to a more wild type of red rosebush. I believe your graft union either died or the wild root stalk came up and took over. In addition, you actually have a winged elm tree growing in the midst of your rosebush. That corky ridge or extra growth along the stem is a characteristic of that plant, thus the common name including “winged.” I would definitely try to prune out the tree, or it will overtake your rosebush and shade it out.