In California, the onion season typically runs early May to mid-October, with peak availability mid-May through late August. Exact weeks shift a little with each year's weather.
Can I pick my own onions in California?
U-pick onion fields are basically unheard of — buy braids and bags straight off the farm stand. The best market weeks are mid-May through late August.
How long does onion season last in California?
about 24 weeks end to end — early May to mid-October. The early and late shoulders are real but lighter; the solid stretch of chalk on the band is the sure bet.