The different species and their respective hybreds produce more or less winter foliage if the weather is mild. They will continue to grow through a mild winter. Plants derived from colder areas are less inclined to winter foliage. The desert plants are more susceptible to bacterial rot than other rhizomatous Iris, especially in warm damp conditions. I try to dry the more southern species out to make them pretty dormant in Summer, but I like to be sure that they have got their roots deep down in order to sustain them better against the drought. The rest I keep enough moisture on to maintain a leaf or two - it makes it easier to break dormancy. Once these Iris start to root in Autumn they will continue their growth cycle unless slowed down by either cold or drought. I dry them out a bit in mid winter for about ten weeks, they are then less likely to rot if cold suspends their growth. The leaves are then fairly irrelevant, if they burn in frost more will grow, just as with other bearded Iris The roots can go very deep -I would guess three feet or more and are designed to be efficiant enough to sustain the plants in desert conditions Peter (UK) On Sun, Nov 27, 2011 at 12:21 AM, Jane McGary <janemcgary@earthlink.net>wrote: > I'm looking for information on the annual cycle of irises in the > Regelia section and their hybrids with Oncocyclus irises, known > sometimes as "Regeliocyclus." When I grew these in frames in large > clay pots, kept dry in summer, they did not make significant leaf > growth until late winter. Now I have them in a raised bed inside an > unheated bulb house, and some of them never really went dormant last > summer, even though not watered, and their leaves are almost full > size now. I don't like to see this, because I can't grow Onco irises, > which make early foliage growth that then succumbs to disease during > our humid winters. Did planting the rhizomes out allow them to reach > down so deep that they had some moisture throughout summer? (The bed > has a commercial woven groundcloth liner over native clay.) Is this > bad for them? >