Angie, "Hello Yellow" is a named cultivar of Asclepias tuberosa that has yellow to gold colored flowers. Usually you see A tuberosa in shades of orange to red, but not on one plant. "Gay Butterflies" is a named cultivar that has different shades of oranges and reds on one plant. Here in Oklahoma, A tuberosa grows wild. You will see clumps of it growing across the prairie areas and on old farm lands. I find it to be quite beautiful. One of my favorite mind pictures is of a clump that I saw that was covered with Great Spangled Frits. Talk about something absolutely beautiful and breathtaking. A tuberosa has smaller, fuzzier leaves than the tropical milkweed, or A curavassica. The tuberosa plants also have a lower, scrubbier appearance. Tropical milkweed is an annual in Oklahoma. I IDed your picture by the leaves and the flower heads. The leaves are bigger than A tuberosa and smoother. The flower heads are more open, and the plants are usually taller than the native milkweed. Hope this helps. I've been checking online this evening, and found 10 seeds for $9.98. I think I'll probably opt for finding some plants and trying again to collect seeds in the fall. I had 2 plants last year, but a gopher decided to eat them before I collected any seeds. Sandy

Hey, I work for a small business in northern Michigan that sells native plants and I'm interested in buying seeds if you can collect some. If you can collect any amount of seed I will pay top dollar for them. Contact me at maxbutlerofficial@gmail.com

I always get oleander aphids on my swamp milkweed - always. Sometimes I rinse them off; sometimes, if I see lacewing eggs or lady bug larva I just leave them alone. It's amazing how quickly a few lacewing/ladybug larva can clean up an infestation. Quite honestly, the plants in my yard that seem to get the highest infestations are the ones in full sun and tend to get stressed during the hottest times of the summer. I have not noticed a correlation between shade and aphid infestations. Right now I have 8 varieties of milkweed in my yard and I have seen aphids on 5 of the 8 species. The ones that seem to get the heaviest infestations are the incarnata and curassavica. I have also noticed that the plants seem very damaged by the apids if they get out of control. The leaves become very dehydrated, are covered with honeydew and sticky. The leaves also become pale, splotchy, and limp and just don't appear healthy. And they get that sooty mold on them if it goes way too long. I try not to let them get that bad - if nature hasn't taken over then I do. ~Laura

I agree with everything dbarron says and would just add to it. These two plants have totally, completely, enormously, almost opposite needs and habits, except that they both want sun and plenty of it. Tuberosa is a long-lived perennial of the temperate zone IF it has well-drained soil. Over-watered or in poorly drained soil, it will suffer root-rot. You cannot keep it in a pot, it has to be planted out in your zone. Curassavica is a tropical species and will not overwinter for you except in a greenhouse or greenhouse-like conditions. It likes lots of water and it exhausts nutrients rapidly, so probably needs feeding to prosper. The eBayer who told you it was hardy to your zone was way off base. As to your original question, why is tuberosa small and falling over while curassavica is tall and erect, that's partly because of light (not enough for tuberosa) and mostly because of habit. Curassavica always grows straight up and erect, and it grows, as dbarron says, like a weed, maturing in its first year to flowering and fruiting (in fact, it does so half-way through its first year). Tuberosa is one of the slowest species of milkweed to mature, never flowering in its first year, often taking up to three years to reach maturity. But tuberosa, if you give it a good sunny spot with decent soil, will reward you for a lifetime, whereas curassavica will evaporate within a year or two.