Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's possible to plant pearl onions by checking out the USDA zone info for Walnut Creek.

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 tend to make it in very little cold which tells us that you can plant them slightly earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pearl onions in Walnut Creek 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. You probably don't want to wait any later than that or else your pearl onions may not have a chance to grow to maturity. You can get started a little bit earlier by starting your pearl onions indoors.

Last Frost Date

In Walnut Creek the average date of last frost happens on February 15. In the coldest months of winter you can expect an average low temperature of 25°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Walnut Creek and it changes from year to year. Half of the time in Walnut Creek last frost occurs after February 15 so just be sure to be ready to cover your pearl onions if you have a surprise late frost.

USDA Zone Info for Walnut Creek

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 Low	25°F
Highest Expected Low	30°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 Walnut Creek

You may be interested in your other planting guides for Walnut Creek.