One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when it's the best time to plant purple rock cress is to use the USDA zone info for Calimesa.

Planting Calendar for Purple Rock Cress

Frost tolerance for purple rock cress:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Purple Rock Cress do ok in cold weather which tells us that you can plant them quite a bit earlier in the year than other frost tender plants.

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

Last Frost Date

On average the last frost has passed is on February 15 in Calimesa. You should expect an average low temperature of 25°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Calimesa is not always accurate and the actual date of last frost changes from year to year. Since half of the time in Calimesa last frost occurs after February 15 be ready to protect your purple rock cress if you have one of those late frosts.

USDA Zone Info for Calimesa

Here is the info for USDA Zone 9b.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	25°F
Highest Expected Low	30°F

This means that on a really cold year, the coldest it will get is 25°F. On most years you should be prepared to experience lows near 30°F.

Plants to Grow in Calimesa

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