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.

The best time to plant purple rock cress in Blair can be figured out by looking at the USDA zone info.

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 do well in cold you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant purple rock cress in Blair 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. Any later than that and your purple rock cress may not have a chance to fully mature. You can get started a few weeks earlier by starting your purple rock cress indoors.

Last Frost Date

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

Keep in mind that USDA zone info for Blair is an average and the actual date of last frost is different every year. Half of the time in Blair it frosts late in the year after April 15 so be sure to be ready to cover your purple rock cress in the event of a late frost.

USDA Zone Info for Blair

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Blair

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