Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Sonora you can determine when it's the best time to plant xerianthemum by looking at the USDA zone info.

Planting Calendar for Xerianthemum

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

Xerianthemum are barely cold tolerant which tells us that you can start planting them slightly earlier than more sensitive plants.

The earliest that you can plant xerianthemum 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 xerianthemum and expect a good harvest is probably September. You probably don't want to wait any later than that or else your xerianthemum may not have a chance to really do well. Starting your xerianthemum indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Remember that USDA zone info for Sonora is just an average and the actual date of last frost is different every year. Half of the time in Sonora you get surprised by a frost after February 15 so be sure to be ready to protect your xerianthemum 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.