TOW: Dormancy, Seed and Bulb
Wed, 14 Jan 2004 21:43:31 PST
Hello all ~

I have only limited experience with geophyte seed -- Narcissus and a few 
others -- but that small amount of knowledge is set forth below.

In general, Narcissus (or daffodil) seed presents no particular problem 
with germination.  Like most seed of this type, it will readily germinate 
(when planted in June soon after harvest) with the cooler temperatures and 
abundant moisture of fall.  If harvested in June but not planted until 
September/October there may be some retarded germination but it isn't 
obvious the following spring.  Only when the seed has been kept out of the 
ground for a year, or longer, before planting will there be retarded 
germination or failure to germinate.  I have done this (for various 
reasons) over the years and found that nothing will appear above ground for 
at least one complete season after planting.  This indicates that the seed 
as it dries in preparation for an extended dormancy develops inhibitors in 
the seed coat.  The seeds go from plump, shiny-black in appearance to 
smaller and matte-black.  The suggestion that seeds be soaked prior to 
planting has never occurred to me to try with year old daffodil seed.  I am 
going to try that in the future to see what happens!  I have a feeling that 
that seed may germinate normally, in season, after the soaking process 
removes inhibitors present in the outer coating that are dependent on 
rainfall to leach out.

Chilling daffodil seed would have no particular effect, I would think, as 
they grow in many areas about the world that do not have particularly cold 
winters.  Tazettas, for example, are native to the countries around the 
Mediterranean and were probably carried eastward by travelers on the Silk 
Road to China.

Some people have reported the development of a few seed in the capsule of 
daffodil stems, after being accidentally broken off at some time after 
pollination but before maturity and kept in water to mature in bright 
indirect light.  It seems to be a race between the decay that sets in at 
the end of the stem and maturation of the seed!

Some of the species present special requirements for germination that are 
similar to the growing conditions required by the species itself; makes 
sense, I guess!  The bulbs of N. cyclamineus must never get dry during 
dormancy or it will perish.  To grow this species well requires that it be 
grown damp and cool (protected from the heat of the summer sun) and I grow 
the seed/seedlings with this requirement in mind.  It, like several others, 
is sensitive to pH and must have a general level below 5.5 to do well.  N. 
rupicola and the species and forms of N. triandrus triandrus also have some 
pH requirements that need to be met.  Although, here both seem to do well 
after a dry dormancy, with NTT shaded during that period from the sun's 
heat but rupicola enduring warmth and bone-dryness.

I should mention that I have had some of the most spectacular lack of 
success with hyacinth.  I've planted the seed within a few days of harvest 
and many months afterward and on most occasions never see sprout one!  The 
seed is odd in that it has a fleshy part attached to it [aril? elasiosome 
(sp)?] like a trillium.  I have planted seed with this thing still fresh 
and I've dried the seed until this too dries and can be rubbed off.  I have 
no idea why it is there as the seed seems quite able to fend for itself 
unless, like trillium, it serves as an enticement to ants to carry the seed 
off away from the parent plant.  The few Dutch growers I know have been 
unusually tightlipped about any "secrets" for getting this seed to grow and 
prosper.  It's not that I don't have seedling bulbs from my years of 
trying, I do, it's just that I really wonder why hybrids of this species 
(orientalis) seem to be so difficult to germinate.

Dave Karnstedt
Cascade Daffodils
Silverton, OR  97381
Cool Mediterranean climate with usually mild wet winters and hot dry summers

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