Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. 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 Northfield can be used to figure out when 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 a lot earlier in the year than other plants that might not handle the cold.

The earliest that you can plant purple rock cress in Northfield 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. If you wait any later than that and your purple rock cress may not have a chance to fully mature. You can get started a little bit earlier by starting your purple rock cress indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Northfield. In the coldest months of winter you should expect an average low temperature of 0°F.

Since the USDA zone info for Northfield is an average the actual date of last frost is different every year. Since half of the time in Northfield it frosts late in the year after April 15 be ready to cover your purple rock cress if you have a surprise late frost.

USDA Zone Info for Northfield

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 Northfield

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