Külmstratifikatsioon

Külmstratifikatsioon, also known as cold stratification, is a horticultural technique used to germinate seeds that require a period of cold and moisture to break dormancy. Many plant species, particularly those native to temperate climates, have seeds that are naturally programmed to germinate in the spring after a winter dormancy period. This dormancy is often broken by exposure to cold temperatures and consistent moisture.

The process typically involves sowing seeds in a moist growing medium, such as peat moss, vermiculite, or sand, in a container. This container is then placed in a cold environment, usually a refrigerator set between 1-5 degrees Celsius. It is crucial to keep the medium consistently moist but not waterlogged, as this can lead to fungal growth or seed rot. To prevent drying out, the container is often sealed in a plastic bag or covered with a lid.

The duration of cold stratification varies significantly depending on the plant species. Some seeds may require only a few weeks, while others might need several months. It is important to research the specific requirements for the seeds being stratified. Once the stratification period is complete, the seeds are removed from the cold and sown as usual, typically in a warm, well-lit environment to encourage germination. This method effectively mimics the natural winter conditions, promoting successful germination for a wide range of difficult-to-start seeds.