How to harvest onion seeds – pro tips on technique, timing, and storage
Timing
Wait until the onion flower heads have dried and turned brown
Let the seeds dry on the plant until they are black, which indicates they are ready to collect
If wet weather is forecast, cut the seedheads earlier (before fully dry) and hang them upside down in a paper bag to dry indoors
Harvesting
Cut the dry seedheads off the plant and place them in a paper bag
Allow the heads to dry further in a cool, dry place for about a week
Shake the bag vigorously to release the seeds
Alternatively, gently crush the dried seedheads by hand or using a fine mesh sieve to separate the seeds from the chaff
Storage
Ensure the seeds are completely dry before storage to prevent mold
Store the dried seeds in a glass jar, seed envelope, or airtight container
Label the container with the variety and date
Keep the seeds in a cool, dark location like a refrigerator to maintain viability
Variety Selection
Stick to collecting seeds from heirloom onion varieties, not hybrids, for best results
Heirloom varieties recommended include 'Yellow Sweet Spanish', 'Red Burgundy', and 'Walla Walla'
By following these tips on timing, harvesting technique, and proper storage, you can successfully collect and save onion seeds for future planting. The process is simple and allows you to grow your favorite onion varieties year after year.