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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.

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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. 

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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.

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

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

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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. 

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G: Highest germination rate in cool soil.

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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.

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I: Legume Inoculant (more info next year)

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J: Legume seeds (more info next year)

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K: Parasitic species which needs a host plant

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L: Plant fresh seed or keep seed moist

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

LOCATION

Located in Massachusetts

Serving New England gardeners

376 Washington Street
Norwell, MA 02061

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