The USDA Zone info is a great tool for gardeners to help us determine 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.

You should be able to figure out when to plant cerastium by checking out the USDA zone info for Caribou.

Planting Calendar for Cerastium

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

Cerastium do well in moderate cold which tells us that you can start planting them earlier than more sensitive plants.

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

Last Frost Date

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

Just be sure to remember that the actual date of last frost is an average because it is based on the USDA zone info for Caribou and it is different every year. Since half of the time in Caribou you get surprised by a frost after May 15 be ready to protect your cerastium if you have a late frost.

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.