One of the best tools that you have as gardeners to help us figure out 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.

It's possible to figure out when to plant purple rock cress by looking at the USDA zone info for Auburn.

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 tells us that you can plant them much earlier than other frost tender plants.

The earliest that you can plant purple rock cress in Auburn 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. If you wait any later than that and your purple rock cress may not have a chance to grow to maturity. If you are starting your purple rock cress indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Auburn. You can expect an average low temperature of 10°F in the coldest months of winter.

Since the USDA zone info for Auburn is just an average the actual date of last frost will vary from year to year. Half of the time in Auburn there is a last frost after March 15 so make sure that you are prepared to protect your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Auburn

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

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

Plants to Grow in Auburn

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