Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The first opportunity to plant begonias in Caribou should be figured out by looking at the USDA zone info.

Planting Calendar for Begonias

Frost tolerance for begonias:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since begonias require warm weather you have to wait until after the last frost before you can plant them.

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

Last Frost Date

On average the last frost is on May 15 in Caribou. 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 changes from year to year. Half of the time in Caribou it frosts late in the year after May 15 so just be sure to be ready to cover your begonias 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.