Experts and BHG readers answer.
Scale and mealybugs on orchids
Insecticidal soap and neem oil are the two best solutions for these pests without resorting to more-processed products.
The key to controlling these pests isn't as much what you use --- but how often you use it. I don't know what your attack schedule is, but the place most gardeners go wrong is that they use the product once and then think they've taken care of the problem.
But, the pests reproduce so quickly, that it's actually best to treat your plants once a week for 4 or 5 consecutive weeks. Constant vigilance will help more than just about anything else.
I hope this helps!
Senior Garden Editor, BHG.com
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