I've only grown D. cistiflora of these. Seed was from Chiltern (U.K.)
and was sown in Spring (more because that's when it arrived, rather
than me thinking it was the right season). It germinated after 45
days and grew through the Summer, and Winter, before dying down. Some
of you might remember me discussing this before - when I came to
repot in Autumn, I couldn't find anything living in the cistiflora
pot - just dead looking bits of stem and root. I still potted up the
bits, and rather surprisingly it grew, so next time I dig them up,
I'll have to look more closely just which bits are alive. The second
half of the same packet was equally happy to germinate a year later
and will soon be going dormant.
-- Clarke Brunt (clarke@brunt.demon.co.uk)