Actually I am 9b, bordering on 10. 'Neon Rainbow' needing a cooler climate than here is very possible, but I usually don't have trouble with Joiner plants. I've lost a few (semi-evergreen) but I believe those still had too much dormancy. Some, especially the uf lines and some doubles, are star performers. In the case of 'Neon Rainbow', I am thinking the trouble is with the Munson influence. Years ago, I moved out what Munsons I had because they gave such poor performance in my garden.
