The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Boston you can figure out when you can plant sorrel by reviewing the USDA zone info.

Planting Calendar for Sorrel

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

Sorrel do well in moderate cold which tells us that you can plant them earlier than other frost tender plants.

The earliest that you can plant sorrel in Boston 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 fully mature. If you are starting your sorrel indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Boston the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -5°F.

It's important to remember that USDA zone info for Boston may not be accurate from year to year and the actual date of last frost changes from year to year. Since half of the time in Boston it frosts late in the year after April 15 be ready to protect your sorrel in the event of a surprise late frost.

USDA Zone Info for Boston

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Boston

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