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

A way of determining when it's possible to plant firebush is to use the USDA zone info for Caribou.

Planting Calendar for Firebush

Frost tolerance for firebush:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

Since firebush require warm weather it is necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant firebush 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 firebush and expect a good harvest is probably August. If you wait any later than that and your firebush may not have a chance to grow to maturity. Starting your firebush indoors is a great way to get them started a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Caribou is an average the actual date of last frost changes from year to year. Since half of the time in Caribou there is a last frost after May 15 be ready to protect your firebush 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.