Winter sowing geophytes

Jane McGary
Wed, 24 Dec 2008 15:19:28 PST
Alani wrote,
One of my original attractions to geophytes was do a frustration with
>difficult seeds. Without heat most seeds just seem to wait until spring and
>natural warmth even in a cool greenhouse. Without even a cool greenhouse the
>only one for here that comes to mind would be garlic chives. Not too
>inspiring I know.

There is a vast literature on seed germination and the different 
temperature cycles that individual genera and even species respond to 
by germinating. Some geophytes germinate in fall as soon as they ahve 
had a period of warm, dry storage and then get moisture, while others 
need one or more multi-month periods of moist chilling (not freezing) 
followed by warmth. In some cases (Cyclamen, for example), fresh 
seeds germinate quite soon, but stored seeds can take several years 
to do so. The most mysterious to me is Colchicum, in which something, 
presumably temperature fluctuations, will trigger germination in 
several species planted in different years within a week of one another.

I wrote a detailed article, also helpfully commented on by John 
Lonsdale, that appeared about 2 years ago in the Rock Garden 
Quarterly vol. 65 no. 3. It covers growing many genera of bulbs (not 
tropical ones, which I don't grow) from seed. It's too long to put in 
our PBS newsletter, but back issues can be purchased at

Jane McGary

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