(i posted this on pest forum too but i figured there might be more traffic here.)
what are these on the seedpods of my butterfly weed? should i kill em or leave em? will they harm my seedpods?
i've found it useless to spray this particular plant. the aphids will be back. the soap does kill them, as tom said, but you'll be spraying all growing season and the soap will kill butterfly larvae also.
i ended up drowning them all in buckets of soapy water. pretty easy. i saw a praying mantis nearby and chastised him for neglecting his duties. my husband said he was probably stuffed already! :)
thanks everyone for your help.