Seed Saving for Cold Hardy Biennials

Biennials are plants that need two years to complete their lifecycle. In the garden, without additional protection, only biennials hardy enough to survive winter will produce seed in their second year. This means that if we continue to save seed from those that do survive, we are selecting for winter hardiness, which has additional benefits, extending the harvest period later into fall/winter and earlier in spring.

Planting for a Two-year Cycle

  • After acquiring seed for a cold-hardy biennial, plant out only half in the spring or summer, saving the other half for the following year. Plants that survive the winter will produce seed and die. Either collect the seed and replant or passively let it reseed itself. Once you have a two-year cycle established in your garden, you no longer have to acquire new seed, and you’ll have extra seed to share!

Selecting for Cold Hardiness

  • Since only the plants that survive winter will be producing seeds, we are selecting for cold tolerance and creating strains of crops that have longer harvest periods in our area. Sharing this locally-adapted seed with others via Oshkosh Seed Savers will give new gardeners a head start in establishing a regenerating supply of culinary biennials in their gardens.

Examples of Cold-Tolerant Biennials 

  • Italian Flat-leaf Parsley is generally more tolerant of cold than the curly-leaf type (and it is more flavorful). The dark-green leaves seem to like the cool of spring and late fall. Rather than use it merely as a seasoning, why not use it as a salad main-ingredient (as in tabouleh) or make a pesto to freeze for the winter months. Siberian Kale (such as “Red Russian”) reliably survive the winter in Oshkosh without protection, and when it does, it usually goes to seed by mid-summer. The second-year leaves will be among the first edible greens in your spring garden; feel free to harvest them before the plant starts to make seed. Young kale is a sturdy salad green, and older leaves are great baked into “chips,” sauteed, blanched, boiled in soups/stews, baked into egg/vegetable dishes. Blanch and freeze your surplus for winter.