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actionclaw

Cold stratification & tricking seeds


When artificially cold stratfiying any seeds that require it, can they be "tricked"? I've read articles, anecdotes, etc. that seem to support both sides of this issue.

(Like the joke about the thermos bottle being able to keep hot things hot and cold thing cold: "How do it know?") How would the seed know whether it's been in the freezer/refrigerator for a week, a month or three?

In nature, they might receive 90 day (or 120 day or whatever) cold stratification due to the length of the seasons but to the "mind" of the seed what's most important: length of cold or the transition from one state to the other? ("I've been cold for 90 days. I've had enough." versus "I was cold; now I'm not. It's go time! )

Comments (6)

  • yiorges-z5il
    12 years ago

    People on the "BOTANY" forum may be able to offer more help.
    There are several reasons for cold stratification (1) to soften or crack the hard seed coat. duration therefore not that important (2) to bring about prompt & even germination... minimum required time after that ..... (3)bring about physiological changes. Themperature & duration very important...Therefore your answer is "all the above""

  • albert_135   39.17°N 119.76°W 4695ft.
    12 years ago

    There are numerous ''tricks''. Freezing, acid treatment etc. As mentioned above take specific questions to Gardenweb's Botany Forum. Or do a Google search on your specific interest with ' site:.edu ' in your search terms.

  • ActionClaw (Northern Ohio zone:5a/5b)
    Original Author
    12 years ago

    Those aren't "tricks" but different types of stratification. I'm aware that different seeds require different types of stratification: scarification (nicking, scratching the outer covering), soaking or using acid to emulate natural wearing/decomposition or in the case of certain seeds even being exposed to fire/extreme heat. In all these cases the reason is usually fairly obvious; in order to allow moisture, etc. to penetrate the outer coating.

    My question pertains specifically and exclusively to "Cold stratification". By "tricking seeds" I'm wondering if the seed can be "fooled into thinking" it's been dormant a season or two though, in actuality, they've only been in the freezer/refrigerator for a week or so.

    If it is merely a matter of expansion, contraction, cold-induced cracking --- a transition from one state to the other and back--- one day'd be as good as 90.

    I always do (usually fairly extensive) research before posting on any forum. On this subject, I mostly found answers to the "what is?s" and "how?s" but not so much the "why?s". Here I thought I might find others with anecdotal experience from experimentation.

    Just as one example, right now I have a large patch of Cilantro/Coriander (Coriandrum sativum) that, though I grew it in order to use the (Cilantro) leaves, has already gone to seed. There's still plenty of growing time left this season. It'd be nice if I could harvest this year's seed, do a "Quickie Cold stratification", plant and get a second crop this year. This is an experiment I plan to be trying .

  • morz8 - Washington Coast
    12 years ago

    Coriander shouldn't need cold stratification at all, although it may germinate better in cooler soils. I could sow more here and expect germination in 1-2 weeks, if you are in one of the areas experiencing excessive heat, those above normal temps could affect (slow) your germination.

  • ActionClaw (Northern Ohio zone:5a/5b)
    Original Author
    12 years ago

    If you look into it a bit you'll find that some sources say Coriander does require Cold Stratification (and my personal experience is that, for whatever reason, I've not had much success with a second crop). I don't really know one way or the other so shouldn't have mentioned it and regret that I did. It simply happened to be on my mind at the time of writing so I provided it as an example ..and apparently not a very good one.

    So please let's "strike from the record" my mention of Cilantro and get back to the original question and how it pertains to an anonymous seed that definitely does require Cold Stratification.

  • lurkandkibitz
    12 years ago