The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of getting a good idea when to plant purple rock cress is to examine the USDA zone info for Princeton.

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.

Purple Rock Cress are one of those plants that can tolerate quite a bit of cold weather which means that you can plant them a quite a bit earlier than other frost tender plants.

The earliest that you can plant purple rock cress in Princeton 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. Starting your purple rock cress indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Princeton. You can expect an average low temperature of -5°F in the coldest months of winter.

Just be sure to remember that USDA zone info for Princeton is just an average and the actual date of last frost will vary from year to year. Since half of the time in Princeton you get surprised by a frost after April 15 be ready to protect your purple rock cress if you have one of those late frosts.

USDA Zone Info for Princeton

Here is the info for USDA Zone 6b.

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

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

Plants to Grow in Princeton

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