Harvest Onion Seeds: How To Collect And Save Onion Seed

Include onion in your home garden, collect the onion seeds when bolting, and save them for the future gardening season. It is one of many ways to keep gardening on a budget.

Onion Seeds

Onion is one of the favourite vegetables to grow by home gardeners. It is relatively easy to grow and easy to care for it.

As an Amazon Associate I earn from qualifying purchases. This post may contain affiliate links. Please see the Disclosure Policy for details.

Any Allium family that includes spring onion, garlic, chive, or leek is the perfect companion plant for most vegetables, fruit, and flowers.

Especially spring onion is one of the easiest herbs to grow. You can just literally put the store-bought onion base leftover from cooking in the garden or container, and then you will have some new shoots of green onions in a short time.

Onion Is A Biennial Plant

A biennial plant is when the plant finishes its life cycle in two years of growing seasons. Some of them consider a tender perennial like snapdragon or hollyhock.

The first year usually grows the plant’s essential things, like roots, foliage, and stems. The biennial plants will produce fruit, flowers, or seeds by the second year.

Biennial plants won’t return in the third year, but most reseed themselves if you don’t remove the flowerhead and collect the seeds.

Onion is also a biennial plant. Growing onion from seed will get a nice spring onion or scallion and bulb in the first year.

Then if you intend to harvest onion seed, you can remove the entire plant and store it overwinter in a cool dark place. Replant it next spring, and the onion plant will send the new green spike and flower stem.

Depending on the weather, onions can also send a flower stem in its first year. The constant change of cold and hot temperature during the day will manipulate the onion into thinking of bolting early. If you find them bolts early, there are still ways to use onion flowers.

Collect Onion Seed For Next Season

Bolted onion is not a bad thing, especially for a home garden. Onion bloom helps your garden by attracting bees and all beneficial insects.

When the onion flower sets to seed, it shows hundreds of black seeds in its whole flower head. If you don’t pick it once the flower head dries up and becomes brownish, those seeds will drop to the grounds, and you will have volunteer seedlings around its parent.

The plants from the seed you collected might not be the same as the variety you planted if it is a hybrid one. Choose the non-hybrid onion plant if you want the same type to grow the following season.

To collect onion seeds for the next season

Harvest the onion seed when the plant is dry. A wet flower head tends to make it mush and create mould.
Cut the flower stem about three inches carefully.
Put the dried-up flower head upside down into the bowl.
Shake the onion flower head off. These seeds will fall into the bowl.
Carefully inspect it to remove any bugs and extras like debris from the onion flower.
Transfer the onion seeds to the paper envelope.

How To Store Onion Seed

Onion seed retains their high germination within one year. Once you save the onion seeds into the paper envelope, write down the plant’s name and variety.

Like most store-bought seed packages, keep the onion seed envelope in a cool and dry place. You will be surprised to get hundreds of seeds from one flower head. Also, you probably will have several paper envelopes just for onion seeds.

My favourite way for seed storage is to keep these envelopes in a used shoebox and put them in the pantry or basement storage shelf.

By next season, you can start planting the onion seed indoors several weeks before the last frost date in your area. You can use the seed-starting essentials or recycle some household items to sow seeds indoors if you are into upcycle projects for gardening.

Grow onion in your garden and collect the seeds for the following growing season. #growingonion #harvestingonionseed #seedsavingtips Click To Tweet