Seed Stratification

As all good gardeners know entirely too well, as soon as the soil warms in spring, there will be an overabundance of new weeds to contend with. These are last year’s flowers’ posterity, just waiting for their opportune moment, waiting for conditions to be just right for germination. By delaying their initiation until spring, they will maximize their growth before having to contend with their first winter. Seeds use a variety of mechanical and chemical tactics to avert germination until their inside says “go outside”.

But not all seeds hibernate. Most seeds sold via commercial catalogs and nurseries have been hybridized for generations and will usually come up as soon as planted. Where the gardener is most liable to run into problems is with seeds of native and woody plants. But for seeds with thick, hard walls, even purchased seeds may need some help.

Faking Winter

What we need is a little pretend winter. It isn’t all that necessary for the seed to spend the cold months in
the ground, as long as it thinks it did. ( How hard could it be for you to ‘trick’ a seed? LOL Put the seeds in a small container with a moist (not wet) medium of vermiculite. You can also use peat or sand. Leaving it in the refrigerator for four or six weeks. This is stratification, simulating natural winter conditions that a seed must endure before germination.


Some seeds are enclosed by a very hard winter coat. The action, known as scarification means somehow, by mechanical, thermal or microbial means, to open the natural seed coating. This process occurs naturally in nature however, gardeners have established ways to imitate this natural processes for the seeds we need to cultivate. While in nature this hard winter coat would eventually be broken down, a gardener can reduce the time it would naturally take by using a file or short knife. If you clip the seed with fingernail clippers, be careful not to clip too deep and damage the seed. The goal is to allow moisture to get in so the seed can germinate.

After scarring, soak for a day in a mix of warm water and milk. Soaking in something acidic (milk contains lactic acid) will break down the seed coating.

Finding What Works

I will be the next question you ask will be, “What process for what seed?” The best answer I can give you is … your local library. Or, you can be a true cyber-gardener, and post a message to the Growing from Seed Forums @gardenweb. Much of the advice you find will be based on the experience of trial and error. And often one authority contradicts another. But gardening isn’t meant to be a purely logical pursuit. For most of us, the learning is the fun.

The Ready Store
"The doctor of the future will give no medicine, but will interest his patient in the care of the human frame, in diet and in the cause and prevention of disease" ~ Thomas Jefferson

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