Seed Stratification

Seeds that in nature would need to survive a winter outside before conditions were right for them to germinate in the spring may require stratification before they will sprout.

“Moist cold” stratification involves putting the seed in a damp planting medium in a tightly covered container (to keep them moist) and chilling in the refrigerator at about 38-40 degrees.

With tiny seed, one way to do this is to mix the seed with a small amount of moist potting soil in a small container, such as a plastic cup, that has a tight cover. After stratification, you just plant a small amount of the seed-soil mixture in its own pot.

Larger seed can be folded into a damp paper towel, which is then put in a plastic bag, tightly sealed, and put in the refrigerator.

The length of time in the refrigerator depends on the plant. It is important that the seed mixture stay moist (not wet), and that the seeds be planted immediately if they begin to germinate – so you’ll need to check your seed every few days to see if any have sprouted.