Answer: Based on your description I am not sure what the bugs were. If washing them off seemed to work, that might be something to try periodically to keep the population to a minimum. To minimize the chance of them overwintering, clean up and remove any plant debris once it has died back completely. It's a good idea to know what the pest is before trying to treat it. If you see them again in spring, please ask again at the Q&A with a bit more information about what they look like and we will try to identify them for you. Another possibility would be to ask about them at your County Extension (445-9792). Butterfly weed is a very tough plant, so I would expect it to come back. Keep in mind that it emerges extremely late in the spring so you might want to mark its location now so that you don't accidently damage it or dig it up or plant over top of it while working in the garden next spring.
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