One of the first steps you take when you are determining your gardening schedule is find your 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 determine when you can plant sorrel by looking at the USDA zone info for Zone 4b.

Planting Calendar for Sorrel

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

You can plant sorrel a little bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant sorrel in Zone 4b is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant sorrel and expect a good harvest is probably August. Any later than that and your sorrel may not have a chance to really do well. You can get started a little bit earlier by starting your sorrel indoors.

Last Frost Date

On average all chance of frost has passed is on May 15 in Zone 4b. It might get as low as -25°F during the coldest months of winter.

It's important to remember that USDA zone info for Zone 4b is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Zone 4b you get surprised by a frost after May 15 be ready to protect your sorrel if you have one of those late frosts.

USDA Zone Info for Zone 4b

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Zone 4b

You may be interested in your other planting guides for Zone 4b.