Beets, a member of the Chenopodiaceae family, are cultivated for their edible root and nutritious greens. Obtaining seeds requires a two-year process, shifting focus from the usual annual harvest. The unique reproductive life cycle means gardeners must actively manage the plant’s environment to encourage seed production. Successfully saving beet seeds ensures a supply of your favorite variety and requires understanding specific steps for plant selection, overwintering, and careful harvest.
Understanding the Biennial Cycle of Beets
The fundamental step in acquiring beet seeds is recognizing the plant’s biennial nature. A biennial plant completes its life cycle over two growing seasons, focusing on vegetative growth in the first year and reproduction in the second. The familiar root and leaves develop during the initial season, followed by the flowering stalk and seeds the next year.
To transition to seed production, the beet must undergo vernalization. Vernalization is the requirement for a prolonged period of cool temperatures to trigger the development of a flower stalk, known as bolting. Beets typically require exposure to temperatures between 37°F and 50°F (3°C and 10°C) for at least 10 weeks to induce flowering.
Once vernalization is met, the plant “bolts,” sending up a tall, branching flower stalk in the second year. The resulting fruit structure, commonly called a beet “seed,” is botanically a dried fruit or utricle, often referred to as a seed cluster. This corky, brown structure typically contains two to six true seeds encased within the dried flower parts.
Selecting and Overwintering Beets for Seed Saving
Seed saving begins with selecting plants that possess desirable characteristics. Choose only the best roots—those that are healthy, disease-free, and exhibit the preferred size, shape, and color for the variety you wish to preserve. This selection process should happen at the end of the first growing season before the first hard frost.
Beets belong to the species Beta vulgaris, which includes Swiss chard and sugar beets. These varieties can easily cross-pollinate, potentially mixing traits. Because beets are wind-pollinated, isolation is necessary to maintain seed purity, requiring distances often ranging from 800 feet to over a mile from other flowering Beta vulgaris plants.
If you live in an area with a mild winter (above 15°F), you may leave the selected roots in the ground under a heavy layer of mulch for protection. For colder climates, the roots must be carefully lifted for indoor overwintering to ensure survival and proper vernalization. Harvest the roots when the soil is dry, gently brushing off the dirt, and trim the tops to about a half-inch above the crown, ensuring the apical bud is not damaged.
The roots should be stored in a cool, dark, and humid environment, such as a root cellar, at temperatures near 35°F and 90% relative humidity. They are often packed in materials like damp sand or wood shavings. In the spring, replant the overwintered roots once the danger of hard frost has passed. Provide ample space, such as 18 to 24 inches apart, to accommodate the large, branching seed stalks that will develop.
Harvesting, Processing, and Storing Beet Seeds
In the second season, the replanted roots produce a tall, multi-branched stalk and flowers, followed by seed clusters. The seeds mature gradually, starting from the bottom of the stalk and moving upward, changing color from green to a dry, tan-brown. The optimal time for harvesting is when roughly two-thirds of the seed clusters on the stalk have turned brown and feel dry to the touch.
To harvest, cut the entire seed stalk or pull the whole plant and move it to a protected, dry location with good air circulation. The stalks should be hung or spread out on a cloth or tarp to cure and finish drying for one to two weeks. This curing time ensures that remaining immature seeds reach full viability and the moisture content is low enough for storage.
Once fully dry, the seed clusters must be separated from the stalk material through threshing. For small batches, running a gloved hand along the stalks will dislodge the clusters into a container. Larger quantities can be threshed by placing the stalks on a tarp and gently treading on them.
The threshed material must then be cleaned. This is typically done by screening to remove large debris and then winnowing to blow away the lighter chaff, leaving behind the heavy seed clusters. The seed clusters must be completely dry before storage. When stored in a cool, dark, and airtight container, beet seed can remain viable for five years or more.