Creating natural awakening processes for seeds artificially is called seed stratification. This procedure can be performed at home. To sow seeds of some perennial plants in the spring, we need to imitate the natural winter conditions, during which a seed that has fallen to the ground is covered with leaves and snow, soaking up moisture and trace elements, while its shell softens in preparation for spring awakening.
What is Seed Stratification
Stratification involves keeping seeds in a moist environment at low temperatures for 2 to 5 weeks. This procedure triggers embryonic dormancy in the seeds, after which, when placed in warm soil, true spring arrives for the seed, leading to active germination. Without prior cooling, the seed may simply rot in the ground.
It turns out that it is advisable to stratify the seeds of all perennial herbs - oregano , thyme , rosemary , lavender , hyssop , lemon balm, tarragon . A year ago, I sowed without stratification, resulting in a large number of seeds not germinating. However, at that time, it wasn’t critical - 2-3 plants per pot were enough. Nonetheless, rules are rules.
How to Stratify Seeds at Home
Seed packets do not always provide instructions regarding the necessity and duration of stratification. Most often, I come across recommendations for stratifying lavender seeds. It is said that this procedure is necessary for lavender - about a month at temperatures between 0 and 5 degrees. One of the readers shared her experience: seeds that underwent cooling sprouted in the second week, and some that did not undergo stratification also germinated well. So now, one might wonder if these antics with the refrigerator are really necessary :).
For oregano, thyme, marjoram , sage , and rosemary, stratification is not required, but if there is doubt about the seed quality, cool them for about 2 weeks. However, stratification is essential for ginseng, hawthorn, pasque flower, primrose, fir trees, thuja, pine, clematis, and gentian (which might be useful for such plants). I couldn’t find a clear and reasonably accurate list of plants that require stratification, even in gardening encyclopedias.
Stratification of seeds at home can be done in the refrigerator. Soak the seeds in a strong solution of potassium permanganate (1 gram of permanganate in 100 ml of water. The color should be dark, cherry-like) for 1 hour, then rinse. If your seeds are branded, coated, pelleted, and pesticide-treated, do not soak them. Large seeds and in large quantities can be mixed with moistened sand, layer by layer, and placed in the refrigerator. I suggest a method for a small quantity of seeds, for modest gardening needs on a windowsill. Using lavender seeds as an example.
Lavender Medicinal Seeds
Lavender has small seeds that cannot be mixed with sand. I relied on the experience of seasoned gardeners: I took a zip-lock bag and wiped it from the inside with hydrogen peroxide. I did not treat the seeds - I had no means to do so, and last year’s sowing experience, disregarding all rules, turned out well. I think it will work out this time as well. Next, I sprayed two cotton pads with filtered boiled water, placed a dozen seeds on one of them, and covered it with the other pad.
I placed it in the bag and into the refrigerator, in the coolest spot under the freezer. There, the temperature averages 1-3 degrees. I will begin to check after 3 days, allowing air into the bag.
There are some recommendations:
- Use meltwater for moistening seeds during stratification (referring to natural snow).
- Spray the seeds with growth stimulators - Epin or Zircon.
- Alternating warm-cold temperatures, gradually raising it. Night in the refrigerator, day on the windowsill.
I will definitely report on the results of the lavender stratification.
