Insects - Lace Bug
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  (May) I have fifty azaleas in a group planting that were all damaged by lacebugs last year. I applied Bayer Advanced Tree and Shrub insecticide this spring. They bloomed nicely and seemed improved, but now I notice several plants have some leaves that are deformed, extremely thick looking, curled, like a growth of some kind on them. Could this be leaf rollers? What can I do about it?

  The problem is azalea leaf gall and has nothing to do with any insecticides or other products that you may have used. Azalea leaf gall is a fungus disorder that occurs in cool, wet springs--which we have had. The problem looks much worse than it actually is. The swollen plant tissues or "galls" are made up of abnormal plant tissue. Infected leaf tissue is usually pale green in color and look almost like candle wax has been poured on them. Later in the season, a white spore layer covers the infected plant parts, and actually reinfects the plants for next season. Galls eventually turn brown and harden as the season progresses. When you see the problem, simply snap off the damaged tissue and dispose of it. If you can control the problem before the white spores form, hopefully you will have less of a problem next season. But then again, if next spring is warm and dry, the problem won't be as severe anyway. Sprays are not needed.

  (September) I need some plant advice. A few months ago I noticed my azaleas leaves looked funny so I asked my local nurseryman to stop by and look at them. He said we had lace bugs and to spray them with Diazinon or Malathion and then again in two weeks. We have done it three times now and so far, one has died and two more are about to go and there are about 10 more (all that are left) are sick. What can we do, if anything, to save them?

  Probably the most common problem statewide on azaleas is lacebugs. Lacebug damage starts in May and really begins to show in August, if they were left unchecked. Lacebugs suck the sap out of the foliage, leaving them with a bronzed appearance, if you have heavy populations. The damage that you see is permanent, and will not go away with any spray program. Sprays, after the fact, are used to stop, or slow down any further damage. The timing of your sprays may have something to do with the dying or damage to the plants -- lacebug typically won't kill a plant the first season. If the plants were stressed -- dry and hot, the frequent sprays may have burned them. For now, no more spraying. Water as needed (luckily all the rains should have taken that need a way for a bit.) Wait and see what the plants look like next spring before replacing. If they were just burned, the old foliage should fall off, and new leaves will appear. Blooms will probably be at a minimum due to the damage. An easy way to prevent lacebug damage would be to use Bayer Advanced Tree and Shrub Insecticide in late February or March. It is used as a soil drench, under the mulch. The plant takes the chemical into its system, and then you have a season of prevention.

  (October) Last year you suggested a chemical to put on azaleas to help protect them against the bronzing leaf color in the summer. I did get some and used it in late February. My azaleas have been absolutely perfect all year, part of it due probably to the rain we have had. However, I give a lot of credit to the recommendation you made. I have forgotten the name of it--and thought perhaps I would recognize it, but so far--and maybe it isn't on the shelves this early--I haven't recognized it. Sure would appreciate if you would list it again. I promise I will list it and save it this time.

  I have had many reports of how effective it was. It was Bayer Advanced Tree and Shrub insecticide, and one application applied in early spring should give you a season free of lacebugs. A great product, but a tad expensive! While there are many who love the product and how easy it is, I have had some requests for some less expensive alternatives. If you have an abundance of azaleas and the price would be exorbitant to treat them all, you can use Di-syston about three times for good control, or Orthene sprays immediately after bloom, and then again for several more applications -- then monitor for problems throughout the season.

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