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.

In Caribou you can figure out when it's a good idea to plant flowering kale by referring to the USDA zone info.

Planting Calendar for Flowering Kale

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

You can plant flowering kale just a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant flowering kale in Caribou 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 flowering kale and expect a good harvest is probably August. You probably don't want to wait any later than that or else your flowering kale may not have a chance to grow to maturity. If you are starting your flowering kale indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Since the USDA zone info for Caribou is just an average the actual date of last frost will vary from year to year. Half of the time in Caribou you get a frost after May 15 so be sure to be ready to protect your flowering kale in the event of 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.