Growing from Seed-PBS TOW

Jane McGary
Thu, 21 Nov 2002 16:41:21 PST
Mary Sue asked,
>Jane, what is the wives tale about snow? Do you think it works?

Some alpine growers claim that melting snow water stimulates germination in
seeds, either because it is particularly pure or because of extra oxygen in
it. I don't know of any test of this theory. It's also possible that the
snow insulates the pot in freezing weather and helps it thaw slowly, which
might help if the seeds are frozen. Once or twice I tried watering
recalcitrant seeds with a product called "Oxy-Plus" that is supposed to
oxygenate the soil, but I don't think it helped.

One thing that has not been mentioned is that even seed that appears to be
good may not be. There are a lot of tiny insects and other organisms that
eat the embryos out of seeds. I don't know how prevalent this problem is
with bulb seeds -- it is very common with composites.

>Uli what is Seramis? 

It is a product available in Europe that is made from porous hardened clay
in granules. I think there is a similar product available in North America,
particularly on the East Coast where they do not have pumice. Pumice would
be an equivalent and is undoubtedly cheaper in most of North America, even
where they have to ship it in. However, it should be mentioned that pumice
will decompose over a period of several years in an acidic environment, so
if you mix it with peat, as I do, it loses its beneficial qualities after 4
or 5 years. This can be noted in seed pots that are kept that long -- and
yes, I do keep some seed pots 5 years, particularly desert irises.

I agree with Alberto Castillo's posting regarding the method of growing
"flat black" seeds. I do almost exactly as he does and have never had any
problems germinating Rhodophiala, etc., whether freshly collected or stored
for a period of a year or more in the refrigerator. (However, I do not grow
tropical species, which may respond differently.) I've always considered
these multi-step methods such as flotation and germinating in bags in the
refrigerator to be space-saving but labor-intensive, and I have more space
than time.

John Lonsdale wrote,
>I also have a question.  Should seed of things like Crocus be allowed to dry
>out during the summer if they don't germinate the first season (usually
>because sown too late) ?  

I don't usually do this deliberately, but Josef Halda once told me that
Eremurus seed in particular should be allowed to dry out during the summer
if it doesn't germinate the first season. If I have seed that I've been
told should have a dry period, I put the pot in my summer-dry bulb frame
instead of on the deck with the other seed pots.

>As an aside, I have just had a pot full of Fritillaria striata seed
>germinate.  This seems very early but  may fit in with its life cycle in
>habitat.  Can anyone comment please ?

I grow some of this species almost every year, since my plants dutifully
set seed, and it typically germinates very early. I keep the pots in the
greenhouse  during freezing weather. F. liliacea, another low-elevation
California species, does the same thing. You need to be on guard against
damping off with these if they are in warmer conditions, but John has an
alpine house, which should be perfect.

Jane McGary
Northwestern Oregon

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