Glossary

Cold stratification is a process in which seeds are exposed to cold, moist conditions for a specified period, mimicking winter weather. For many native plant species, this chilling period is necessary to break seed dormancy and trigger germination when conditions warm.

In the Santa Cruz Mountains, plants like Western Goldenrod (Euthamia occidentalis) and Western Columbine (Aquilegia formosa) naturally drop their seeds in fall. Those seeds remain on or just beneath the soil surface, enduring winter rain and cold until sprouting in spring.

Gardeners can replicate this natural process by:

• Sowing seeds outdoors in fall and allowing nature to take its course
• Or using refrigeration: mix seeds with moist sand or vermiculite, seal in a container, and store in the fridge—typically for 4–8 weeks, depending on the species

Cold stratification ensures that seeds wait to sprout until spring, when conditions are more stable, thereby reducing the risk of early germination during brief winter warm spells.

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