One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 common way of getting a good idea when to plant borage is to consult the USDA zone info for Zone 10a.

Planting Calendar for Borage

Frost tolerance for borage:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Borage tend to make it in mild cold which means that you can plant them a little bit earlier in the year than more sensitive plants.

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

The last month that you can plant borage and expect a good harvest is probably October. Any later than that and your borage may not have a chance to fully mature. If you are starting your borage indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is January 31 in Zone 10a. You should expect an average low temperature of 30°F in the coldest months of winter.

Since the USDA zone info for Zone 10a may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Zone 10a last frost occurs after January 31 be ready to cover your borage if you 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 Low	30°F
Highest Expected Low	35°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 your other planting guides for Zone 10a.