One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By referring to the USDA zone info for Sonora it's possible to estimate when you can plant digitalis.

Planting Calendar for Digitalis

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

Since digitalis do well in moderate cold you can plant them a little bit earlier in the year than other plants that might not handle the cold.

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

Last Frost Date

In Sonora the average date of last frost happens on February 15. It might get as low as 20°F during the coldest months of winter.

Since the USDA zone info for Sonora is an average the actual date of last frost changes from year to year. Half of the time in Sonora you get a frost after February 15 so always be ready to protect your digitalis if you have a surprise late frost.

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.