Great to see some species irises Leslie!
Teresa, other than my potted irises, I grow most of mine in raised beds or on inclines with grit added to the soil because of the heavy clay we have here. I have a few planted in good garden soil in full sun (12+ hours per day in summer) with good drainage and they do fine too. The dwarfs prefer a bit more shade and moisture than the TBs during hot periods. Come to think of it, I never had rot in any of my little ones, but I did have some just dry up - maybe there's a lesson there?
