Does anyone grow Asclepias Physocarpa?
I don't know how far to space them. I've read they get up to 6' tall but sources vary on width: 2' to 6'.
How do they grow in your garden and in what conditions (sun/shade/etc.)?
Here is a link that might be useful: A. physocarpa, aka Balloonplant, Swanflower, et al