You're right that the damage is always worse in sunny locations. I've had the best control using neem extract in oil - there are several brands. As for timing, check with your local extension service or a local rhodo nursery. These pests don't usually appear until warm weather, if we ever get any this year.

The objective of using horticultural oil is to smother the overwintering eggs and nymphs. Treatments should have begun over the winter and into the spring. Hopefully, that sort of prophylactic care interrupts the cycle, and you avoid another major outbreak altogether!

Anyway, you could use it anytime, before the bloom period and after. Read and follow the directions carefully for whatever product you purchase, and make sure that the stuff gets to the underside of the leaves, and the twigs.

OK, I'm going to try the oil. I think I know a nursery that might be able to help me out with some advice on spraying it.

The blooms are just about over here in PA. I think I'm going to hack the one back and transplant it next week to a shadier spot, the pieris will have to tough it out with the spraying.... it seems to be growing nicely but gets the darn bugs and they make it look horrible.

On the other hand I could wait until warm weather brings the bugs out before I do anything.... Like you said Mainegrower, the way it's going I might have plenty of time to think it over!

Thanks again for the help.

BTW, there are 2 types of horticultural oil - one light for spring and summer, the other is a fall/winter oil. Please dont use the heavier oil in summer, dont make the plant struggle more than it needs to. Yep, smothering by oil has killed plants, esp during our extremely warm summer days.

Be warned, many store staff dont know the difference and will say that there is none, not true. Read the label, timing of application is listed, Follow it.

If someone has used winter oil and hasnt had a bad outcome, it may reflect more of the climate, plant resilience, etc. A favorable outcome may mean that lady luck is in play, not that the 2 oils are identical.

happy gardening to all,
Gull

Ahhhhh. I wondered about that. I read that there were different types of oil and then was told at the garden center they were all the same. Serves me right for going to the "other" place and asking questions. It's amazing how bad advice can stay with you even if you suspect you know better.

I tried the Bayer systemic tree and shrub insecticide this year and it has worked like a charm. In years past I went thru alot of trouble spraying volk oil on my azaleas ( I have over 100) and for the most part have eliminated the pests, but I have one area where the azaleas are so thick it was near impossible to get full coverage on the backs of the leaves. The bayer product is mixed with water and poured into the root zone, and after having noticed in early spring the signs of lace bugs I applied the Bayer product and have seen no signs of further damage. It is quite expensive though. I paid about $20 to treat five bushes.