One of the first steps you take when you are determining your gardening schedule is find your 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.

The USDA zone info for Grand Junction can be read to estimate 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.

Since purple rock cress are very cold tolerant you can plant them much earlier in the year than other frost tender plants.

The earliest that you can plant purple rock cress in Grand Junction 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. Starting your purple rock cress indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Grand Junction. You should expect an average low temperature of 0°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Grand Junction may not be accurate from year to year and the actual date of last frost is different every year. Half of the time in Grand Junction there is a last frost after April 15 so always be ready to protect your purple rock cress if you have a late frost.

USDA Zone Info for Grand Junction

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Grand Junction

You may be interested in your other planting guides for Grand Junction.