I read up some more about the cold hardiness of this plant, and it's listed as a tender perennial, but also listed as being hardy in Zone6b to below zero temps. I'm confused.

How does it overwinter in your area?

Sherry

Sherry,

I've never had mine return, even though it looked like it made it through the winter and was still green. So I replant every year. You are in a warmer zone than I am, so it may make it. My experience is that it can't handle below zero temps here. It can tolerate mild frosts without damage.

Sandy

Thanks for the information, Sandy!

I went ahead and planted the two that were due to be potted up to the next size - A. physocarpa really grows fast, top and bottom, doesn't it?
The freezes here are pretty rare and nearly always mild, usually not below 30 degrees. However, it occasionally goes below that point, so I may lose these. Last year we had two late, though mild freezes. I put buckets over the plants, and they sailed through, completely undamaged. If a freeze is expected, I think I'll cut it back to the height of the bucket and cover it. I'll overwinter the others in their containers, which are big now.

Sherry

Sherry,

I can't speak to whether the plants will over winter for you but they are so easy to germinate and grow, if it were me, I'd certainly try a few in ground, just to see if they will overwinter there. I'm like you in that this milkweed holds up far better for me through the dog days of summer and on into fall than any other milkweed I've grown.

I also read up on another similar plant, gomphocarpus fruticosus, aka swan plant or cotton bush. The seed pods have a bit of a point on the end, otherwise the seed pods closely resemble 'Oscar'. The leaves are thinner and this plant is supposedly a bit more cold tolerant.

I have germinated some seed of this plant to see how it compares to Oscar. I think Oscar will be better for producing food for the Monarch cats because it has a larger leaf. But I like to try new plants so am having a look at this variety of milkweed.

I've also just about decided to go strictly with the silky gold tropical Milkweed here, as it holds up the best in my weather conditions.

Mary

That's interesting about the Silky Gold holding up best, Mary - you wouldn't think it'd make any difference if it was that one or the red one.

Several of my A. physocarpa have flower buds on them, so I should get seeds. You're right, they're very easy to grow from seed!

Sherry