How to Screen and Winnow Seeds
After the Harvest, Low-Tech Tools Simplify Seed Saving

Gardeners who save seed, or grow and harvest grains, know that separating seeds from their pods or husks can be a time-consuming job. While large industrial growers use machines to thresh and winnow seed crops, home seed savers can look to a number of simpler tools to accomplish the task. Once cleaned, seeds stored in moisture-proof containers can last for several years.

Here are a few devices for separating seeds from debris and chaff:

• Pillowcase or Cloth Sack - Perhaps the most common method of hand threshing. Place seed pods in the sack and thrash (“thresh”) it against a hard surface to break the seeds from their coverings.

• Boards - Place harvested seed pods between two boards and apply gentle pressure to crack open the pods. Take care not to press so hard you split the seeds.

• Screens or Strainers - Screens with meshes of varying sizes provide a quick way to separate debris from seeds. Even using a single screen is a vast improvement over hand picking. Screens work especially well for seeds (such as lettuce) that do not have pods. A set of graduated screens will cut out about 80 percent of the hand work. You can build screens yourself or order seed cleaning screens from sources like Horizon Herbs.

• Wind Power - Outside on a breezy day, drop seed from one container into another and let the wind blow away the unwanted chaff.

• Electric Fan - While wind can be fickle and blow your chaff in unexpected directions, a fan set on low will produce a steady stream of air for winnowing.

• Gravity - This works well for round seeds. Use gravity to help roll seeds down a newspaper into a container. The heavier seeds roll down, while the chaff remains behind.

Below, seed saver and year-round gardener, Celt Schira, demonstrates how she uses screens, the wind, and gravity to help separate the chaff from garden sage seeds:

Slideshow: Screening and Winnowing Seeds

Seed saver, Celt Schira, writes about gardening and self-sufficiency on her blog: Celt’s Garden.

More seed saving articles:
How to Save Tomato Seeds
Saving Seeds, Sowing Food Security
Planning a Seed Saving Garden