When can I plant Pearl onions in Zone 10a

The USDA Zone info is a great tool for gardeners to help us figure out our gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for our area.

One way of estimating when it's the best time to plant pearl onions is to consult the USDA zone info for Zone 10a.


Planting Calendar for Pearl onions

Frost tolerance for pearl onions: Tolerant of a very small amount of frost.
When you should plant them: Up to 3 weeks before last frost.

Pearl onions are barely cold tolerant which means that you can get them planted just a bit earlier than other frost tender plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant pearl onions
Possibly ok, but a risky time to plant pearl onions
Probably not a good time to plant pearl onions

The earliest that you can plant pearl onions in Zone 10a is February. However, you really should wait until March if you don't want to take any chances.

The last month that you can plant pearl onions and expect a good harvest is probably September. Any later than that and your pearl onions may not have a chance to grow to maturity. Starting your pearl onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in Zone 10a. In the coldest months of winter we should expect an average low temperature of 30°F.

Since the USDA zone info for Zone 10a is an average our actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 10a we get surprised by a frost after January 31 be ready to cover your pearl onions if we have a surprise late frost.

USDA Zone Info for Zone 10a

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)January 31
Average Date of First Frost (fall)December 15
Lowest Expected Low30°F
Highest Expected Low35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Zone 10a

You may be interested in our other planting guides for Zone 10a.