How to Gather & Plant Onion Seeds

• Step 1

  Gather ripened bulbs for seed production and transport in bags to curing area. When onions have gone to seed, their stems will produce buds, or heads, filled with seeds. In his guide "The Home Production of Onion Seed and Sets," W. R. Boattie recommends harvesting before the onion plant dries out in the field to prevent the first seed from shattering when you handle it. This occurs in most places no later than August 15. Cut the onion heads, leaving 2 to 6 inches of stem intact.

• Step 2

  Cure your onion seeds in a dry area with good circulation. Arrange the onion heads in thin layers on mesh-bottomed drying racks. Stir your curing seeds often to promote circulation. When the seeds are completely dry, shell by hand to remove chaff and reserve seed for spring planting. Plant well-cured onion seed within two years for best results.

• Step 3

  Plant your cured seeds in seed-starting planters eight to 12 weeks before planting outdoors. In her article "Growing Onions," Beth Jarvis suggests planting three seeds in each starter cell and covering with about 1/4 to 1/2 inch of starting media. Water your seedlings often.

• Step 4

  Harden off your seedlings before planting. Jarvis suggests gradually exposing your seedlings to longer periods of outdoor weather over the course of two weeks. Plant seedlings every 4 inches. The soil should just cover the seedlings' bulbs.

• 1
• Mature onion plants Bags for seed-gathering Mesh-bottomed drying rack Seed-starting kit
• Mature onion plants
• Bags for seed-gathering
• Mesh-bottomed drying rack
• Seed-starting kit

References & Resources

• The Home Production of Onion Seeds and Sets
• Growing Onions