One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A way of figuring out when you can plant broccoli is to consult the USDA zone info for Caribou.

Planting Calendar for Broccoli

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

Broccoli do well in a little bit of cold which tells us that you can plant them a little bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant broccoli 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 broccoli and expect a good harvest is probably August. If you wait any later than that and your broccoli may not have a chance to really do well. Starting your broccoli indoors is a great way to get them started a few 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 the actual date of last frost is an average because it is based on the USDA zone info for Caribou and it will vary from year to year. Half of the time in Caribou there is a last frost after May 15 so just be sure to be ready to cover your broccoli if you have a surprise 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.