One of the first steps you take when you are getting a good idea 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.

One way of getting a good idea when you can plant purple rock cress is to check out the USDA zone info for Walnut Creek.

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.

Since purple rock cress do well in cold you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant purple rock cress in Walnut Creek 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. 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 couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Walnut Creek. It might get as low as 25°F during the coldest months of winter.

Since the USDA zone info for Walnut Creek is not always accurate the actual date of last frost changes from year to year. Half of the time in Walnut Creek there is a last frost after February 15 so make sure that you are ready to protect your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Walnut Creek

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 Walnut Creek

You may be interested in your other planting guides for Walnut Creek.