Q: 1. My variegated euonymus has lots of little white dots under the leaves and it doesn’t look very healthy. Can you diagnose?
2. I have a row of golden euonymus shrubs that have developed scale on the leaves and a few of the short stems. If I cut the back the foliage drastically now, will this harm the shrubs?
A: In my experience, a heavy infestation of scale on euonymus is almost impossible to control without major pruning to remove the majority of the leaves and insects first.
Euonymus grows vigorously, so pruning any time between spring and early fall won’t hurt it terribly. You’ll get some regrowth before winter but lots more next spring.
I recommend applying systemic insecticide (Bayer Tree and Shrub Insecticide) in spring and also spraying what’s left of the shrub with horticultural oil three times per year (April, June, September) (be sure to follow label directions for hot weather application).