Q: I think aphids killed my milkweed this year. It came up and immediately
orange aphids attacked it. I’ve been rubbing them off of the stems every day
that I saw them but I stopped in fear of killing the monarch caterpillar eggs.

A: Since your plants could have aphids and monarch butterfly eggs on it
simultaneously, I don’t recommend using insecticides at all. The best three
alternatives are to rub them off with fingers or a stiff brush, wash them off
with a strong stream of water, or plant nearby lots of plants that attract
beneficial insects. I see dozens of ladybugs on my bronze fennel and carrot
plants when they bloom. You can find other lists of plants like this online.