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

You will be able to estimate when it's the best time to plant purple rock cress by using the USDA zone info for Woodburn.

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 very cold tolerant which means that you can get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant purple rock cress in Woodburn 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 really do well. If you are starting your purple 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 March 15 in Woodburn. In the coldest months of winter you should expect an average low temperature of 15°F.

Since the USDA zone info for Woodburn is just an average the actual date of last frost will vary from year to year. Since half of the time in Woodburn there is a last frost after March 15 be ready to cover your purple rock cress in the event of one of those late frosts.

USDA Zone Info for Woodburn

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°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 20°F.

Plants to Grow in Woodburn

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