Dear James, I can only confirm what Alberto and Chuck said: They love heat, where I am, temperatures regulary go up to 40 C during summer and rarely drop below freezing in winter with frost only occuring rarely. As for sun, mine are grown under a 40% shadecloth and in spite of our low humidity, they are thriving. I plant them in 25 cm plastic pots and they are huge (up to 1,5 m) and flower througout summer, as a matter of fact they had a flush of flowers today, they are the most magnificent shade of blue! When Mary Sue have set up a page for the genus, I will add some photos of mine. As for the other species, I only have N.gracilis, but they seem to prefer much deeper shade that N.caerulea. The other species seem to be hard to find or not available at all! If anyone grows them or knows who does, please let me know! Happy bulb-seed-and-jumping-iris! Regards, Pieter van der Walt Hartbeespoort, South Africa