When to Plant Pearl onions in Orinda, CA

Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant pearl onions in Orinda can be determined by referring to the USDA zone info.


Planting Calendar for Pearl onions

Frost tolerance for pearl onions: Tolerant of a very small amount of frost.
When to plant: 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 more sensitive 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 Orinda 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 really do well. Starting your pearl onions indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Orinda. In the coldest months of winter you can expect an average low temperature of 25°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Orinda and it can change quite a bit from year to year. Since half of the time in Orinda last frost occurs after February 15 be ready to cover your pearl onions if you have one of those late frosts.

USDA Zone Info for Orinda

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)February 15
Average Date of First Frost (fall)December 15
Lowest Expected Low25°F
Highest Expected Low30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Orinda

You may be interested in your other planting guides for Orinda.