Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Sonora can be reviewed to determine when it's a good idea to plant saxifraga.

Planting Calendar for Saxifraga

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

You can plant saxifraga slightly earlier in the year because they are one of those plants that can tolerate a tiny bit of cold weather.

The earliest that you can plant saxifraga in Sonora 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 saxifraga and expect a good harvest is probably September. If you wait any later than that and your saxifraga may not have a chance to really do well. If you are starting your saxifraga indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on February 15 in Sonora. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Sonora is an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Sonora last frost occurs after February 15 be ready to cover your saxifraga if you have 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.