Onion seeds are not difficult to grow and harvest. The only thing to keep in mind is that onions are biennial, which means they only produce seeds every two years. By growing onion seeds in your garden, you can create a stash to plant next year. The seeds of onions can also be eaten directly or sprouted to include them in a healthy diet.
Steps
Step 1. Plant the onions and leave them in the ground for two years
The second year, in late summer, umbrella inflorescences will form with small purple, white or yellow flowers, depending on the variety.
If you also want to have a supply of onions to eat during the first year, plant a few more
Step 2. Wait for the flowers to dry
When most of the inflorescences dry out, the seeds will begin to fall off on their own.
Step 3. Cut the buds and let them dry completely
Step 4. Separate the seeds from the stems and other elements that form the inflorescences
Many seeds will come off on their own. To collect the rest, close the buds in a bag and hit it against a hard surface. If the seeds are many, you can try to use the force of the wind to separate them from the stems and other elements that make up the inflorescences. Swirl the flowers over a large container or quickly switch them from one container to another when you are outdoors and there is a light breeze. The air should blow away the stems that are very light, while the seeds that are heavier should fall into the container.
Don't worry if parts of the buds fall into the container along with the seeds, unless you want them to sprout. They will decay once placed in the ground when you plant the seeds
Step 5. Store the seeds in a cool, dry place
Write the date on a label or directly on the bag. If the climate is mild, the seeds can be planted immediately. Keep in mind that they should be used within a year to get the best possible result, but you can have an acceptable germination rate even during the second year.
Advice
- Onions are biennial. Those you intend to eat must be harvested in the same year as sowing. To collect the seeds, you need to wait for the second year. If you want to both eat onions and get seeds, plant twice as much.
- If you plant several varieties of onions you can get cross-pollinated, which means that from the seeds you could get a variety that is different from the ones you planted. It won't be a problem if you intend to sprout the seeds, grow spring onions or get onions of different varieties. If, on the other hand, you want to get the same type of onions from the previous year, you will need to take precautions to avoid cross-pollination or buy specific seeds.
