One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The earliest that you can plant purple rock cress in Forest Grove can be determined by using the USDA zone info.

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 get them planted much earlier than plants that are more sensitive to the cold.

The earliest that you can plant purple rock cress in Forest Grove 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. Starting your purple rock cress indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on March 15 in Forest Grove. It might get as low as 15°F during the coldest months of winter.

Since the USDA zone info for Forest Grove is just an average the actual date of last frost will vary from year to year. Half of the time in Forest Grove there is a last frost after March 15 so be sure to be ready to protect your purple rock cress if you have one of those late frosts.

USDA Zone Info for Forest Grove

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 Forest Grove

You may be interested in your other planting guides for Forest Grove.