How to Grow Onion Sets


The American hamburger isn't complete without a slice of onion included. They're great sautéed or raw, as you prefer. This vegetable, often considered a condiment, is fresher, sweater and juicier when taken from your own garden. Onions can be grown from seed, but it is a much longer process than growing them from onion sets. Onion sets are small onion bulbs that are planted in early spring and then harvested when they have grown to a mature size.

Step 1

Prepare the garden soil in a sunny location before planting your onion sets. The healthiest onion will be exposed to at least six hours of sunshine per day. Dig up the soil, to a depth of approximately 8 inches, with your shovel. Mix in a bit of compost to create a nutritious soil. Rake the area evenly.

Step 2

Create a furrow by using the corner of your hoe to make a long row in the soft soil. Dig a small hole for each onion bulb, deep enough to cover the bulb, leaving the green sprout above the soil. Cover the bulb with soil. Press down on the soil to compact it around the onion bulb, until it is stable. Leave a space of about 4 inches between each bulb. This space may vary, according to the onion variety you choose. Always follow the manufacturer's suggestions for planting.

Step 3

Water the newly planted onion sets thoroughly. Keep the soil moist, but not muddy. Keep the area weed free, so the onions are not competing for the soil nutrients. The composted soil should provide enough nutrients. However, if you wish you can apply a monthly fertilizer. Seaweed-based fertilizer is excellent for onions.

Step 4

Pull the onions out of the ground, for use, a week after the green stalks fall over and dry up, turning yellow and brown. This will occur in the fall. They should come out easily by pulling up on the stalks. However, you may loosen the soil around the onion if this proves difficult.

Step 5

Shake the soil off the onions. Lay them out on an elevated screen or other dry location for a couple of days, protected from rain or other moisture. This allows the mature onions to cure.

Step 6

Clip off the stalk to an inch above the onion. Trim the roots, but do not cut into the onion itself. Store the onions in a well-ventilated, cool location. Place them in a container that has air holes on the sides and bottom. Elevate the bottom of the container so air can flow through the bottom.

Tips and Warnings

  • Do not remove the onion skins when harvesting. If you do, it will invite organisms and decay to the onion flesh. The onions may also be placed in a mesh bag and hung in a cool location for storage.

Things You'll Need

  • Onion sets
  • Shovel
  • Rake
  • Hoe
  • Seaweed fertilizer (optional)
  • Screen (optional)
  • Garden clipper or trimmer
  • Ventilated container or mesh bag


  • The Garden of Eden: How to Grow Onions from Onion Sets
  • Gardening Patch: Growing Onions
  • Gardening Know How: Find How to Grow Onions in Your Garden
Keywords: onion sets, growing onions, gowning onions from sets

About this Author

Karen Ellis has been a full-time writer since 2006. She is an expert crafter, with more than 30 years of experience in knitting, chrocheting, quilting, sewing, scrapbooking and other arts. She is an expert gardener, with lifelong experience. Ellis has taken many classes in these subjects and taught classes, as well.