One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By reviewing the USDA zone info for Caribou you should be able to figure out when it's the best time to plant polka dot plant.

Planting Calendar for Polka Dot Plant

Frost tolerance for polka dot plant:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's probably not a good idea to plant polka dot plant until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant polka dot plant 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 polka dot plant and expect a good harvest is probably August. Any later than that and your polka dot plant may not have a chance to grow to maturity. Starting your polka dot plant indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

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

It's important to remember that USDA zone info for Caribou is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Caribou you get surprised by a frost after May 15 be ready to cover your polka dot plant in the event of 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.