When to Plant Rock Cress in Zone 3a

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The earliest that you can plant rock cress in Zone 3a should be estimated by checking out 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 are very cold tolerant which tells us that you can plant them much earlier than more sensitive plants.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant rock cress
Possibly ok, but a risky time to plant rock cress
Probably not a good time to plant rock cress

The earliest that you can plant rock cress in Zone 3a 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. Any later than that and your rock cress may not have a chance to grow to maturity. 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

The average date of last frost is May 15 in Zone 3a. In the coldest months of winter you should expect an average low temperature of -40°F.

It's important to remember that the actual date of last frost is just an average because it is based on the USDA zone info for Zone 3a and it can change quite a bit from year to year. Half of the time in Zone 3a you get a frost after May 15 so always be ready to protect your rock cress if you have a surprise late frost.

USDA Zone Info for Zone 3a

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-40°F
Highest Expected Low-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in Zone 3a

You may be interested in your other planting guides for Zone 3a.