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.

It's possible to determine when it's the best time to plant sorrel by reviewing the USDA zone info for Riverside.

Planting Calendar for Sorrel

Frost tolerance for sorrel:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Since sorrel are one of those plants that can tolerate a little bit of cold weather you can plant them just a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant sorrel 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 sorrel and expect a good harvest is probably September. You probably don't want to wait any later than that or else your sorrel may not have a chance to grow to maturity. If you are starting your sorrel indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

In Riverside the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Just be sure to remember that USDA zone info for Riverside is just an average and the actual date of last frost will vary from year to year. Since half of the time in Riverside last frost occurs after April 15 be ready to protect your sorrel if you have 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.