One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. 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 making a decision about when to plant purple rock cress is to refer to the USDA zone info for Virginia.

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 tend to make it in a bit of cold which tells us that you can plant them quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant purple rock cress in Virginia is March. However, you really should wait until April 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 August. Any later than that and your purple rock cress may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your purple rock cress indoors.

Last Frost Date

On average the last frost has passed is on May 15 in Virginia. You can expect an average low temperature of -35°F in the coldest months of winter.

Since the USDA zone info for Virginia is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Virginia it frosts late in the year after May 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 Virginia

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-35°F
Highest Expected Low	-30°F

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

Plants to Grow in Virginia

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