Before planting it is a good idea to find your USDA Zone info to determine 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.

A common way of figuring out when you can plant rock cress is to use the USDA zone info for Walnut Creek.

Planting Calendar for Rock Cress

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

Rock Cress can survive in quite a bit of cold which tells us that you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant 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 rock cress and expect a good harvest is probably October. Any later than that and your rock cress may not have a chance to grow to maturity. Starting your rock cress indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average the last frost has passed is on February 15 in Walnut Creek. In the coldest months of winter you can expect an average low temperature of 25°F.

Since the USDA zone info for Walnut Creek may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Walnut Creek last frost occurs after February 15 be ready to cover your 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.