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.

You will be able to determine when it's the best time to plant rock cress by referring to the USDA zone info for Imperial.

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 are one of those plants that can tolerate quite a bit of cold weather which means that you can start planting them much earlier than other frost tender plants.

The earliest that you can plant rock cress in Imperial 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. You can get started a little bit earlier by starting your rock cress indoors.

Last Frost Date

On average all chance of frost has passed is on January 31 in Imperial. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for Imperial 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 Imperial you get a frost after January 31 be ready to protect your rock cress in the event of a late frost.

USDA Zone Info for Imperial

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Imperial

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