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

A common way of figuring out when to plant purple rock cress is to refer to the USDA zone info for Richmond.

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.

You can plant purple rock cress much earlier in the year because they are very cold tolerant.

The earliest that you can plant purple rock cress in Richmond 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. You probably don't want to wait any later than that or else your purple rock cress may not have a chance to grow to maturity. Starting your purple rock cress indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Richmond the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for Richmond is just an average the actual date of last frost will vary from year to year. Half of the time in Richmond you get a frost after April 15 so always be ready to cover your purple rock cress if you have one of those late frosts.

USDA Zone Info for Richmond

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 Richmond

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