Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Caldwell should be looked at to determine when it's a good idea to plant purple rock cress.

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 are very cold tolerant which tells us that you can get them planted much earlier than more sensitive plants.

The earliest that you can plant purple rock cress in Caldwell 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 purple rock cress and expect a good harvest is probably September. If you wait any later than that and your purple rock cress may not have a chance to fully mature. You can get started a little bit earlier by starting your purple rock cress indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Caldwell. You can expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Caldwell may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Caldwell last frost occurs after April 15 so be sure to be ready to cover your purple rock cress if you have a late frost.

USDA Zone Info for Caldwell

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Caldwell

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