Reply #8: Scale can be a bit tougher

[Lone_Star_Dem]

If it's just now showing signs I'd suggest scraping off the adults (the ones in the waxy casings) and squishing them. Spinosad actually does kill the immature scales, only spray it on the infestation NOT the whole plant. The best control is to spray your plants down in the early spring or winter (when they're still dormant) with a nice horticultural oil. That's what I have to do with my roses here. How I hate scale! In this case an insecticidal soap or a nice neem based product is really your best weapon. Spray (infested areas only!) when temps are at their lowest (evening) and hose the plant off before the sun and heat hits them again in the morning. These products will burn in our climates!

Now, I know you don't want to hear this, but if the infestation is bad enough sometimes the best way to deal with it is to prune (don't faint on me!) the infected (adult) scale away and bring in some extra predators (oldier beetles, lady bugs, etc.).

Ack! Scale is the one vermin I still shudder to deal with. Really, a nice dormant oil in the winter is the best defense you have against it in a healthy butterfly garden.