Blooming Onions

Most folks want to grow onion bulbs NOT onion flowers! I have to admit, I let these youngins get way too big and should have picked them when they were little.

They look like leeks! I was in the garden when the Captain came home and he saw these on the ground and asked if we were having leek soup for dinner!

Ok, let's say you did not let them mature like I did. What causes bulb onions to send up flower stalks?
Flowering of onions can be caused by several things but usually the most prevalent is temperature fluctuation. An onion is classed as a biennial which means it normally takes 2 years to go from seed to seed. Temperature is the controlling or triggering factor in this process. If an onion plant is exposed to alternating cold and warm temperatures resulting in the onion plant going dormant, resuming growth, going dormant and then resuming growth again, the onion bulbs prematurely flower or bolt.

The onion is deceived into believing it has completed two growth cycles or years of growth in its biennial life cycle so it finalizes the cycle by blooming. Flowering can be controlled by planting the right variety at the right time. Use only transplants that are pencil-sized or smaller in diameter when planting in early spring or always plant seed, NEVER transplants, in early fall. I wonder if this is true for San Diego's climate. I'm learning so much!