How to Plant a Sprouted Onion

If you’ve noticed your onions growing green onion tops, don’t throw them away. Grow your own onions from your sprouting onions. Some people wonder if you can still eat sprouting onions. You definitely can, as long as the onion isn’t soft or growing mold, but set a few aside for planting.


Steps for Planting Sprouted Onions

If you’d like to try planting sprouted onions, but you don’t have any, just buy some onions at the store and let them sprout at room temperature. Once you see sprouts, follow these steps for planting them:

  • Remove the papery skin of the onion.
  • Cut the onion lengthwise, just until you see the center sprout formation.
  • Carefully, peel off the layers of onion surrounding the inside sprout that grows from the base of the onion bulb.
  • Separate multiple sprouts for planting individually.
  • Place the sprout stems in water until you see roots forming. If your onion stems already have roots, you can plant them directly in soil.
  • Once the roots grow, plant the onion sprouts root side down in a sunny location in your garden or in containers filled with potting soil. Eight to 12 inch pots or containers with one onion each have the best results.
  • Keep the soil moist but not soaking wet.
  • Gradually, let your onions adjust to the sun. After two weeks of filtered light, move them to a sunny location.

How Long to Grow Sprouted Onions

As your onions grow, you can either use the green onions or scallions by cutting them off the onion, or let them grow until they form mature onion bulbs.

If you decide to let your onions mature, leave them in the garden or pot until you see the bulbs pushing up from the soil. The onion tops will start to tip over. At this point, cure the onions by pulling them out of the soil and let them dry completely. You can tell they’re dry when the tops turn brown and crisp.

If your onion sprouts start flowering, let the seeds pods grow. Collect the seeds before they fall out of the pod and use them for planting more onions.