I have very little experience with milkweed, as it has been relegated to hedgerows and uncultivated farmland, where it semms to thrive.
Texokie has stated that there are some 85 varieties of milkweed in his latest Master Gardner newsletter that are native to Oklahoma.
It seems that only certain varieties of milkweed attrack only certain species of butterflies
A lepidopterologist(studies butterflys, habitat and behavior) would be at college or univeristy entomology dept.; a lepidopterist is strictly a collector of butterflys.
Almost all my experience is with horticulture and problems ,diseases and pest control - propogation of weeds (misplaced flowering plants) is not my forte.
A university lepidopterist would be the best and most knowledgeable source of information on milkweed propagation and habitat, and about butteflys .
Well there you have it. Thanks for the info.