Re Iris unguicularis: For a number of years I've grown it in the ground in an entryway greenhouse that goes to 15oF, where it blooms off and on through the winter, and I guess whenever else it feels like it. More recently I put it in a sunhouse that goes to 0oF (pretty weird, huh?). also in the ground. It hasn't bloomed yet but is doing nicely. It is less floriferous in pots in the bigger greenhouse, 32oF min. temp. I've recently started shearing off the leaves in late summer to show off the flowers -- it didn't seem to hurt the plants but otherwise hasn't had much affect. Jim Jones Lexington, MA