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

In Riverside you can determine when it's the best time to plant rock cress by checking out the USDA zone info.

Planting Calendar for Rock Cress

Frost tolerance for rock cress:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Rock Cress do ok in a bit of cold which means that you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant rock cress in Riverside 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. You probably don't want to wait any later than that or else your rock cress may not have a chance to grow to maturity. You can get started a little bit earlier by starting your rock cress indoors.

Last Frost Date

The average date of last frost is April 15 in Riverside. You should expect an average low temperature of -10°F in the coldest months of winter.

Remember that USDA zone info for Riverside is an average and the actual date of last frost is different every year. Since half of the time in Riverside it frosts late in the year after April 15 be ready to protect your rock cress in the event of one of those late frosts.

USDA Zone Info for Riverside

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°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 -5°F.

Plants to Grow in Riverside

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