I planted 6 milkweed last year, which supported at least 30 monarchs throughout the season. The aphids were a terrible problem; I didn't want to spray with neem oil which would affect the monarch egg-laying. I couldn't keep up with removal of the aphids by hand. I do not want the milkweed to attract aphids to the point that the aphids would then jump onto my nearby Japanese maples, azaleas, and hollies. I'm thinking of digging up the milkweeds and putting them in containers, away from my other plantings. Question: could the aphids on the milkweeds jump onto my other plants that are next to them in the landscape? (I may just dig them up and dispose of them, because I do not want an aphid problem in my garden.)
Recommendations from Ohio and South Dakota Extension services: Aphids Spoiling Monarch Milkweeds Are Aphids on Milkweed Really a Bad Thing? Looks like you don't have to worry about the aphids spreading to other plants in the landscape.
Ok thanks very much. So the bottom line of these two articles is that these particular aphids dine only on milkweeds and butterfly weeds. I’ll give them another season, continue removing them with my gloves, and refrain from spraying with neem oil so as not to discourage monarch egg laying. I’ll just step up the manual removal of the aphids, to 2x daily. I do love seeing the monarchs flit around my butterfly garden. Thanks for these articles!! I will share them with my garden center, which recommended I remove the milkweeds if I were so concerned about the aphids possibly jumping to my nearby azaleas. Thanks!
Perhaps judicious application of a soap spray via a narrow, confined stream on plant stems where the aphids tend to congregate would be quicker and cleaner than squishing them by hand.
