One of the first steps you take when you are estimating your gardening schedule is find your USDA Zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of making a decision about when it's a good idea to plant pearl onions is to examine the USDA zone info for Brentwood.

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.

You can plant pearl onions slightly earlier in the year because they are barely cold tolerant.

The earliest that you can plant pearl onions in Brentwood 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 really do well. Starting your pearl onions indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is February 15 in Brentwood. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Brentwood is not always accurate the actual date of last frost will vary from year to year. Half of the time in Brentwood it frosts late in the year after February 15 so just be sure to be ready to cover your pearl onions if you have one of those late frosts.

USDA Zone Info for Brentwood

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 Brentwood

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