Carrots thrive in colder climates and grow best in daytime temperatures ranging from 60 to 65°F. Carrot seeds should be sown directly in early spring, and your seeds will germinate in soil temperatures as low as 55° F. Hardy vegetables tolerate cold temperatures, it is best if their seeds germinate in fresh soil, and seedlings can generally survive severe frosts. Plant these seeds or transplants two to three weeks before the average last spring frost date; they will grow in daytime temperatures as low as 40 degrees Fahrenheit.
Arugula seeds germinate in soil temperatures as low as 40° F (4° C) and young plants are able to survive a light frost. Many of them, such as kale, leeks, carrots, collard greens and Brussels sprouts, actually get sweeter after a few frosts. The cold climate causes them to convert their starches into sugar, which makes them even more delicious. Improper freezing can kill some seeds, but others may be less fussy.
In fact, many wildflower, tree, and shrub seeds require a cold period, or stratification, before germinating. In cold climates, plants such as milkweed, echinacea, nine-bark, sycamore, etc. It will drop seeds in autumn, then it will remain dormant under the snow for the winter. In spring, rising temperatures and humidity will cause these seeds to sprout.
However, without the previous cold and dormant period, seeds like these will not sprout. This stratification period can be easily simulated in a freezer. Hardy vegetables are those that can survive temperatures as low as 20° F before they are finally killed. These vegetables include cabbage, broccoli, Brussels sprouts, carrots, kale, leeks, kohlrabi, and turnips.
When thawed, these hardy vegetables will continue to grow in frost. Remember, too, that even when the cold kills the tops of vegetables such as carrots and turnips, the roots will remain in good condition if the plants are covered with a generous layer of insulating material, such as hay or leaves. This will prevent the soil from freezing and allow you to harvest fresh roots as desired during the winter. However, mice may first discover and enjoy their stash of wintering products.
It is not true that if seeds are frozen they will no longer be viable: seed banks around the world freeze seeds for long-term storage. Read on to learn more about storing seeds in the freezer and using frozen seeds properly. That's why seed companies can send seeds without special protection, even in the worst winter cold, without fear for their survival. Tolerant to cold weather, parsnip seeds can be sown directly in the garden when the soil temperature is 40°F (4°C) or higher.
Seeds should dry completely before freezing, as the freezing process can cause wet seeds to crack or split. You can sow beet seeds directly in the garden as soon as the soil has thawed and they will survive near-zero temperatures. The key to success when freezing seeds is to store the dried seeds in an airtight container and maintain constant cold temperatures. As a home gardener, you probably don't have a cryogenic chamber in your garden shed, and you probably don't need to store thousands of seeds for decades either.
We conserve and promote the culturally diverse but endangered heritage of America's orchards and food crops for future generations by collecting, cultivating, and exchanging seeds and heir plants. Placing spinach seeds in the garden early means you could enjoy your first harvest just as warm-season crops are planted in the ground. Lindsay Sheehan is a lifelong writer, researcher and gardener who loves little more than the thrill of nourishing living things from sleeping seeds. Whether you're storing seeds for a few weeks for successive plantings or for use within a year or two, there are a few steps you should take when using frozen seeds.
Seed banks store rare, exotic and heritage seeds in refrigeration units or cryogenic chambers to ensure the survival and future of specific plant varieties. I like to pre-germinate my pea seeds to make sure I get a good germination rate, but you can also sow them directly in the garden. Storing the seeds in the freezer will provide the seeds with more consistent temperatures than storing them in the refrigerator. .