Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

In Missoula you can estimate when it's a good idea to plant sorrel by checking out 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 are moderately cold tolerant which tells us that you can start planting them earlier than more sensitive plants.

The earliest that you can plant sorrel in Missoula 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. Any later than that and your sorrel may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your sorrel indoors.

Last Frost Date

On average the last frost is on April 15 in Missoula. You should expect an average low temperature of -15°F in the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Missoula and it changes from year to year. Half of the time in Missoula you get surprised by a frost after April 15 so just be sure to be ready to protect your sorrel in the event of one of those late frosts.

USDA Zone Info for Missoula

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Missoula

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