The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By looking at the USDA zone info for Olympia you will be able to figure out when it's the best time 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.

Since rock cress are very cold tolerant you can plant them earlier in the year than other frost tender plants.

The earliest that you can plant rock cress in Olympia 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 fully mature. You can get started a couple of weeks earlier by starting your rock cress indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on March 15 in Olympia. It might get as low as 10°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for Olympia and it can change quite a bit from year to year. Half of the time in Olympia you get surprised by a frost after March 15 so always be ready to cover your rock cress if you have one of those late frosts.

USDA Zone Info for Olympia

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 Olympia

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