The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

One way of estimating when it's a good idea to plant purple rock cress is to examine the USDA zone info for Vernon.

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.

Since purple rock cress are very cold tolerant you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant purple rock cress in Vernon 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 fully mature. Starting your purple rock cress indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Vernon the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of 5°F.

Always keep in mind that USDA zone info for Vernon is an average and the actual date of last frost will vary from year to year. Half of the time in Vernon you get a frost after April 15 so be sure to be ready to protect your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Vernon

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°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 10°F.

Plants to Grow in Vernon

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