I must have grown C. coum at least a half dozen times over the past ten years. They always make cute little cormlets, with a few promising leaves. Then I stick them in the ground in my nursery area, in a nicely protected spot - never to be seen again. Do I need to keep these in pots for a year? Any other secrets to growing these to maturity?
Following up on a request for a bit more information: I garden in Pennsylvania, zone 6. My nursery area has clay soil that has been amended with organic matter over the years, to the point where it's a fairly consistency. I've tried various exposures, but have usually opted for a bed that has dappled shade when trying to keep C. coum alive.
I've never tried to grow these on the east coast. I think there are a couple of key questions.
1. Is anyone having success with these on the east coast?
If not, is it because of
1. summer rain and heat, or
2. winter cold, or
3. both, or
From http://en.wikipedia.org/wiki/Cyclamen_coum : "Along with C. hederifolium and C. purpurascens, C. coum is one of the hardiest cyclamen species, growing well in an area of New York where the temperature has reached as low as −19 °F (−28 °C)." So that answers my first question.
In the Pacific NW, these plants grow and bloom from late Fall to late Spring, then go dormant. So it seems to me that they would be stressed in the Northeast US because of the cold winters and hot, wet summers. I would probably try growing them under deciduous trees, where they will be shaded in summer, and where the soil will get fairly dry between rains because of the tree roots. I would make sure the leaves aren't covered by tree leaves or mulch. I would also make sure the soil pH is up around 6 or higher, by adding lime.
I have always grown Cyclamen in soil that has been modified by adding lots of sand. So I don't know how they would do in clay.
That's my best guess. Does anybody know from experience? Here is some interesting info from a grower in West Virginia:
Here is another one: http://www.saga.co.uk/saga-magazine/december-2011/candy-frosting-192.aspx