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.

By using the USDA zone info for Negaunee you should be able to figure out 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.

You can plant purple rock cress much earlier in the year because they are very cold tolerant.

The earliest that you can plant purple rock cress in Negaunee 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. If you are starting your purple rock cress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Negaunee. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Negaunee may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in Negaunee you get a frost after April 15 be ready to cover your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Negaunee

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 Negaunee

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