Before planting it is a good idea to find your USDA Zone info to figure out 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.

The USDA zone info for Caribou should be used to estimate when it's the best time to plant balsam.

Planting Calendar for Balsam

Frost tolerance for balsam:	Not tolerant of frost.
When to plant:	After the last frost.

You really shouldn't plant balsam until after the last frost when the weather gets warmer because they do not do well in cold weather.

The earliest that you can plant balsam in Caribou is May. However, you really should wait until June if you don't want to take any chances.

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

Last Frost Date

The average date of last frost is May 15 in Caribou. You should expect an average low temperature of -30°F in the coldest months of winter.

Keep in mind that USDA zone info for Caribou may not be accurate from year to year and the actual date of last frost changes from year to year. Half of the time in Caribou there is a last frost after May 15 so make sure that you are ready to cover your balsam if you have one of those late frosts.

USDA Zone Info for Caribou

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Caribou

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