Iris lazica, cretensis, and unguicularis were all unharmed here last winter with prolonged freezing below 0F. I grow I lazica in shade where it flowers well in April. both in damp and dry places. In hotter positions I find it dies out after a few years. Iriss unguicularis seemed to sulk in the Spring after such a cold winter. Pacific Coast Iris divisions do well potted deep with loose garden compost in Automn. They need to develop roots before they are allowed to freeze. Iris douglasii derivitives seem toughest. It is best to use large divisions. They die very quickly in pots if they run out of food. I have had problems with bare root purchases too. Peter (UK) On Thu, Feb 9, 2012 at 12:54 AM, Jane McGary <janemcgary@earthlink.net>wrote: > At my former garden in the Cascade foothills, where winter lows were > usually about 15 F and occasionally a few degrees lower, I grew Iris > lazica and I. cretensis in the ground in well-drained soil, and they > suffered no damage and flowered well. > > I. lazica seems to grow best with some afternoon shade (it is very > drought-tolerant), but it flowered better in full sun. I. cretensis > got a little shade in the morning. > > SPeaking of irises, last fall I bought some Pacific Coast hybrid > irises that were shipped to me bare-root. I planted them in a > well-drained spot the day they arrived, but the majority of them have > failed to grow. Never again! > >