They could be in a state of changing, or your plants could have a chemical on them. Where did you purchase? Never buy from anyone but a local nursery, preferably one that specializes in butterflies.

Have fun! But when the butterflies emerge, they will not going to be bound to your garden. They have wings and can fly away. I don't like caterpilars much. They are ugly and chew up on my plants. So if I spot them, just take them away, far away. Despite that, there are a lot of butterflies around my garden. They are the pretiest insects with an ugly past (wink, wink)

I am a avid orchid grower and have been for many years. I encourage new people to be successful growing orchids. I have been a member of GW for almost as long as it existed. Many people visit the orchid forum for help with their orchid, usually their first or received as a gift. Orchid growing is not complicated but unless you learn a bit about their biology and native environments, you will not succeed and will stop growing these incredible plants. Basic 'dirt' knowledge doesn't really help when you are growing orchids. Most of our 'old timers' have little patience for newbies. Their responses tend to be beyond what most new growers can comprehend. I always try to encourage these people and give just the very basics so they will save their plant and hopefully have flowers the following year. I have found when you encourage people with simple instructions it works and they tend to research more and become 'addicted' to the hobby and learn as they move along. Success is always addictive. I realize it becomes so boring and repetitive to keep responding to people who yell 'help' and have no idea what they are doing. But if the ultimate goal is to educate and encourage, you have to take a deep breath and be kind and instructive in a simple way. Who knows what will happen. The ultimate goal is to encourage people to save these beautiful creatures and to continue to learn. Jane

I can only tell you what I did to, hopefully, solve my MW aphid problem. Mine had gotten so bad, the leaves were turning yellowish. I cut the plants back severely (I didn't have caterpillars at the time), put the debris in the garbage, and sprayed insecticidal soap all over the leaves and aphids that were left. It killed the aphids, but I noticed that some of the leaves withered, like maybe the insecticidal soap was too much for them, too. So, I cut the MW back some more and began just killing the few aphids left by squishing the leaves they were on with two fingers. I check again, and if I miss one I squish that one, too. The MW/Asclepias curassavica grew back rapidly with lots of pretty new leaves, and, since that time, I inspect the leaves every day, and, if I find aphids I squish them. This doesn't hurt the leaves, just turns my fingers yellow. I don't miss a day, because it's amazing how so many can come back so quickly! I also quit using insecticidal soap, because there's no use depending on something that might kill the monarchs in order to kill the aphids. I was lucky to have monarch cats in spring this year, and I might get some in the late summer or fall, the usual time for me to get monarchs. 'Hope this helps! Sherry