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 USDA zone info for Westminster can be reffered to in order to figure out when to plant rock cress.

Planting Calendar for Rock Cress

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

You can plant rock cress quite a bit earlier in the year because they are very cold tolerant.

The earliest that you can plant rock cress in Westminster 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 rock cress and expect a good harvest is probably September. 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 little bit earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Westminster. You should expect an average low temperature of 0°F in the coldest months of winter.

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 Westminster and it changes from year to year. Half of the time in Westminster last frost occurs after April 15 so make sure that you are prepared to cover your rock cress if you have a late frost.

USDA Zone Info for Westminster

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 Westminster

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