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.

It's possible to figure out when to plant sorrel by checking out the USDA zone info for International Falls.

Planting Calendar for Sorrel

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

Sorrel are one of those plants that can tolerate a little bit of cold weather which means that you can plant them earlier than other frost tender plants.

The earliest that you can plant sorrel in International Falls 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 couple of weeks earlier by starting your sorrel indoors.

Last Frost Date

In International Falls the average date of last frost happens on May 15. In the coldest months of winter you can expect an average low temperature of -40°F.

Since the USDA zone info for International Falls is not always accurate the actual date of last frost changes from year to year. Half of the time in International Falls you get surprised by a frost after May 15 so always be ready to protect your sorrel in the event of a surprise late frost.

USDA Zone Info for International Falls

Here is the info for USDA Zone 3a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-40°F
Highest Expected Low	-35°F

This means that on a really cold year, the coldest it will get is -40°F. On most years you should be prepared to experience lows near -35°F.

Plants to Grow in International Falls

You may be interested in your other planting guides for International Falls.