Gardenplanner

Onions that send up a flower stalk

An onion that forms a flower stalk has stopped growing its bulb and won't store well.

When we suggest this

  • Your noteYou noted the stage: flower stalk.

What would stop us suggesting it

  • If it's still open after its window, it shows as overdue for up to 2 weeks, then closes.
  • When you mark it Done or Doesn't apply. "Doesn't fit my setup" stops it for that plant this season.

What to do

  1. Pull the onions that have sent up a flower stalk.
  2. Use them in the next few days instead of storing them.
  3. Leave the rest of the planting to keep growing.

What we can't know

  • How many plants have bolted.
  • Why they bolted. Sets or transplants wider than about 5/8 inch bolt more often.

Based mainly on one university source (UC Master Gardeners); other sources we checked don't address bolted onions.

Where this advice applies

All US regions.

Any US garden growing bulb onions.

Bolting is more common from large sets or transplants.

Exceptions

  • Onions you're growing for seed or flowers.
  • Plants you've marked finished.

Sources

  1. UC Master Gardeners (UC ANR), The Backyard Gardener blog. Harvesting and Storing Onions from the Garden. Accessed September 25, 2026
  2. Utah State University Extension. Onions in the Garden. Accessed September 25, 2026

Reviewed

Sources checked Sept 2026 · awaiting expert review

Gardenplanner research (AI-assisted), pending extension-qualified review

Rule id and version: onion.flower-stalk@1