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.

The USDA zone info for California should be read to determine when it's possible to plant borage.

Planting Calendar for Borage

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

You can plant borage a little bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant borage in California 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 borage and expect a good harvest is probably September. If you wait any later than that and your borage may not have a chance to grow to maturity. Starting your borage indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in California. It might get as low as -5°F during the coldest months of winter.

Since the USDA zone info for California is an average the actual date of last frost will vary from year to year. Half of the time in California last frost occurs after April 15 so make sure that you are prepared to protect your borage if you have a surprise late frost.

USDA Zone Info for California

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in California

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