The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of making a decision about when you can plant borage is to examine the USDA zone info for Sonora.

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 do well in moderate cold.

The earliest that you can plant borage in Sonora 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 grow to maturity. You can get started a couple of weeks earlier by starting your borage indoors.

Last Frost Date

On average the last frost has passed is on February 15 in Sonora. It might get as low as 20°F during the coldest months of winter.

Keep in mind that USDA zone info for Sonora is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Sonora you get surprised by a frost after February 15 so make sure that you are ready to cover your borage in the event of one of those late frosts.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sonora

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