Save Onion Seeds
Onion seeds are not usually difficult to grow or to collect. The only thing to keep in mind is that onions are a biennial, meaning that they seed once every two years. By growing and saving your own onion seeds, you can develop a healthy reserve of seeds for next year's garden, for eating directly, or for sprouting.
Steps
- Plant onions, and leave them in the ground for two years. Watch for flowers and then seed heads to form during the late summer of the second season.
- You may wish to plant extra plants if you want onions to eat during the first season.
- Wait for the seed heads to dry. Most of the flowers will be dry, and the seeds will begin to fall out on their own.
- Cut the seed heads, or umbels, from the plants and allow them to dry completely.
- Separate the seeds from the stems and other matter that makes up the seed head. Many seeds will fall out on their own. For the rest, place them in a bag, pound the whole bag against a hard surface. If you have many seeds, you may be able to use the wind to separate them from stems and other matter. Use a large bowl and toss them in the air, or pour them from one container to another in a light breeze. The wind should sift the lighter stems away and leave the heavier seeds to fall.
- There's no harm in having a little bit of stem or seed head in your seeds unless you are sprouting them. If you plant it along with the seeds, it will just decompose.
- Store the seeds in a cool, dry place. Label the seeds with the year you saved them, or plant them immediately in a mild climate. Most seeds work best if they are used within one year of saving them, but you may get an acceptable germination rate the second year.
Tips
- Onions are biennials. For onions you will eat, you will harvest the same year that you plant. If you want seeds, you will have to wait a second year. If you want both seeds and onions to harvest, plant extra plants for two years running.
- Onions will cross-pollinate if they are grown close to other varieties of onions. That means that you may not get what you started with. If you're sprouting or growing the seeds as spring onions, or if you're willing to try growing onions from the genetic grab bag, that may not matter much to you. If you need the same variety as last year's onions, you must either take steps to prevent cross pollination or buy seed from a source that does.
Things You'll Need
- Garden snips, secateurs, or similar device for plant cutting
- Container to catch seeds
- Bag to keep seeds
