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Seed Stratification Codes

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Stratification Codes

Most native seeds need "cold, moist stratification". That just means winter...OR a winter-like experience. See the codes below to see how to ":unlock" the germination in seed you purchase from us.

More details about winter seed sowing can be found here.

As an example, if you seed has code "A" on it you can plant any time, no winter needed.

If your seed has code C(60) on it, that means it needs a 60 days period of cold, moist "weather".

Feel free to email us with any questions. 

A: Seed should germinate when sown in a warm location.


B: Hot water treatment: Bring water to a boil, remove from heat, pour over seeds, and soak for 24 hours.. Generally this is for seed with a thick seedcoat.


C: (# of days of cold moist stratification) Seeds germinate after a period of cold, moist stratification. Mix seeds with a handful of damp vermiculite or clean sand (moist—but not wet). Place mixture in a sealed plastic bag and store in a refrigerator, NOT the freezer.

D: Sow on the surface of the soil. Generally these seeds are very small.

E: These seeds need a 60-90 day warm, moist period followed by a 60-90 day cold, moist period. 

F: These seeds need a 60-90 day cold, moist period followed by a 60-90 day warm, moist period followed by a 2nd cold, 60-90 day moist period. 

G: Highest germination rate in cool soil.

H: Seeds need scarification: One way this can be achieved is to rub the seed between two sheets of sand paper. If code "C" is also called for, scarify first.

I: Legume Inoculant (more info next year)

J: Legume seeds (more info next year)

K: Parasitic species which needs a host plant

L: Plant fresh seed or keep seed moist

M: Best results when seed sown outdoors in the fall for a natural winter.

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