How to properly stratify perennial seeds in a garden under snow?
Under natural conditions, seeds are stratified if there are a lot of them (for example, you collected your own) and they are not very small. It’s better not to take risks with purchased seeds (and there are only a few of them in bags): sow them at home to avoid troubles that can happen to seeds in the open air.
And there they can be blown away by the wind, pulled under melt water to such a depth from which they cannot break through, and birds can peck them. Seeds can also be destroyed by our unstable winter weather: frosts after prolonged thaws, lack of snow.
Now you are aware of possible failures of seed stratification under natural conditions. But if there are a lot of seeds, you can take a risk.
So, seed stratification under natural conditions begins in winter, when it is cold and snowy in the garden.
Sow the seeds at home in fairly large pots so that in the spring the soil in them remains moist longer and the crops do not die. It is advisable to sow in a mixture free of weed seeds (peat, steamed soil). After sowing, make notes on the pots or in a notebook so that in the spring you know which plants to expect to sprout. After sowing, carefully water the soil and leave the pots warm for two days so that the seeds swell.
Then the pots, having placed them in boxes, are moved to the site and buried in the snow somewhere under the trees so that in the spring they do not end up in the sun. Before this, the boxes with pots are covered with non-woven material to protect the crops from birds, wind blowing and rapid loss of moisture in the spring. When the snow melts, the boxes are transferred to the shade and wait for shoots.
If you have a cold loggia or veranda in your apartment, you can stratify the seeds there. Seeds are sown in small containers, watered, covered with a plastic bag or placed in a transparent cake box.
After allowing the sown seeds to stand in a warm place for two weeks, they are taken out to a cold loggia. On frosty days, so that the seeds do not suffer from sub-zero temperatures, the containers are insulated. On sunny days, increase the ventilation of the loggia to reduce the temperature to optimal (+4 -4 degrees).