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 determining when you can plant purple rock cress is to examine the USDA zone info for Gypsum.

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 a lot earlier in the year because they do well in cold.

The earliest that you can plant purple rock cress in Gypsum 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 really do well. If you are starting your purple rock cress indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Gypsum. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Gypsum is just an average the actual date of last frost changes from year to year. Since half of the time in Gypsum you get surprised by a frost after April 15 be ready to protect your purple rock cress in the event of a late frost.

USDA Zone Info for Gypsum

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Gypsum

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