The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 Milwaukee should be used to estimate when it's the best time 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.

Purple Rock Cress can survive in quite a bit of cold which tells us that you can plant them a lot earlier in the year than more sensitive plants.

The earliest that you can plant purple rock cress in Milwaukee 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 grow to maturity. You can get started a couple of weeks earlier by starting your purple rock cress indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Milwaukee. In the coldest months of winter you should expect an average low temperature of -15°F.

Always keep in mind that USDA zone info for Milwaukee is not always accurate and the actual date of last frost is different every year. Half of the time in Milwaukee it frosts late in the year after April 15 so just be sure to be ready to protect your purple rock cress in the event of a late frost.

USDA Zone Info for Milwaukee

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Milwaukee

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