One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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 earliest that you can plant rock cress in Princeton should be figured out by referring to the USDA zone info.

Planting Calendar for Rock Cress

Frost tolerance for rock cress:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Rock Cress do well in cold which tells us that you can plant them a quite a bit earlier than more sensitive plants.

The earliest that you can plant rock cress in Princeton is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant rock cress and expect a good harvest is probably August. If you wait any later than that and your rock cress may not have a chance to fully mature. If you are starting your rock cress indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Princeton the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Just be sure to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Princeton and it will vary from year to year. Half of the time in Princeton last frost occurs after May 15 so always be ready to cover your rock cress if you have a late frost.

USDA Zone Info for Princeton

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Princeton

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