doglover,
the schubertii are supposed to be hardy to this area and from my experience are, but only to a limited extent. I usually plant them in the fall and have a fine presentation the following late spring...but that's it, they've never successfully overwintered to return a 2nd season for me. They attain probably at least twice the size of christophii. Atm full spread, they're at least basketball size. I've never had one reseed or self seed. If you'd like some seed, I check some out after work and let you know.
