Before planting it is a good idea to find your USDA Zone info to figure out 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.

You should be able to estimate when it's possible to plant tree onions by looking at the USDA zone info for Brawley.

Planting Calendar for Tree onions

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

You can plant tree onions just a tiny bit earlier in the year because they do ok in moderate cold.

The earliest that you can plant tree onions in Brawley 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 tree onions and expect a good harvest is probably September. Any later than that and your tree onions may not have a chance to grow to maturity. You can get started a little bit earlier by starting your tree onions indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Brawley. In the coldest months of winter you should expect an average low temperature of 25°F.

Since the USDA zone info for Brawley may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Brawley last frost occurs after February 15 be ready to cover your tree onions if you have a surprise late frost.

USDA Zone Info for Brawley

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 Brawley

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