How To Grow Onions In Your Garden

onions  in the garden
Image by Pixavril

By Heather Rhoades

Growing big onions in your garden is a satisfying project. Once you know how to grow onions, it is not hard to add these fun vegetables to your garden.

How Do Onions Grow?

Many people wonder how do onions grow. Onions (Allium cepa) are part of the Allium family and are related to garlic and chives. Onions grow in layers, which are essentially an extension of the leaves of the onion. The more leaves that are out of the top of the onion, the more inside the onion layers there are, meaning that if see lots of leaves, you know you are growing big onions.

How to Grow Onions from Seeds

Onions grown from seeds take longer than other methods. If you are in an area with a shorter season, you will need to start the onion planting season by sowing seeds indoors and transplanting to the garden.

Sow the seeds in a location with full sun and good drainage 8 to 12 weeks before the last frost for your area. Cover the seeds with 1/2 inch of soil. Water as needed until it is time to transplant.

If you wish to grow onion sets from seeds, start these in your garden in mid to late July and dig up after the first hard frost. Allow to air dry before you store the onion sets in a cool, dry place for the winter.

How to Grow Onions from Sets

Onion sets are onion seedlings started late in the onion planting season the year before and then stored from the winter. When you buy onion sets, they should be about the size of a marble and firm when squeezed gently.

The onion planting season for set starts when the temperatures get to be around 50 F. Choose a location that get at least 6 – 7 hours of sun a day. If you would like to growing big onions, plant the sets 2″ into the ground and 4″ apart. This will give the onions plenty of room to grow large.

How to Grow Onions from Transplants

If you wish to be growing big onions, then your best bet is to grow onions from transplants. Transplanted onions grow larger and store longer than onions grown from sets.

Once the last frost date has passed the onion planting season begins. Harden the seedlings off before moving the seedlings out into the garden. Transplant the onions to their beds. The chosen location should be in full sun and well drained. Push the seedlings just far enough in the soil to get them to stand up. Plant them 4″ apart.

Watering well is necessary to growing big onions. Onions need at least 1″ of water a week until harvested.

Knowing how to grow onions will make it easy to add these wonderful vegetable to your garden.

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