The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant lobelia in Caribou should be estimated by using the USDA zone info.

Planting Calendar for Lobelia

Frost tolerance for lobelia:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Since lobelia are very cold tolerant you can plant them quite a bit earlier in the year than other frost tender plants.

The earliest that you can plant lobelia 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 lobelia and expect a good harvest is probably August. Any later than that and your lobelia may not have a chance to really do well. If you are starting your lobelia 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. It might get as low as -30°F during the coldest months of winter.

It's important to remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Caribou and it will vary from year to year. Since half of the time in Caribou you get a frost after May 15 be ready to cover your lobelia 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.