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.

A way of getting a good idea when it's a good idea to plant coleus is to consult the USDA zone info for Great Falls.

Planting Calendar for Coleus

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

It's not a good idea to plant coleus until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant coleus in Great Falls 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 coleus and expect a good harvest is probably August. You probably don't want to wait any later than that or else your coleus may not have a chance to really do well. You can get started a few weeks earlier by starting your coleus indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Great Falls. In the coldest months of winter you should expect an average low temperature of -30°F.

It's important to remember that USDA zone info for Great Falls may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Great Falls it frosts late in the year after May 15 so just be sure to be ready to cover your coleus in the event of a surprise late frost.

USDA Zone Info for Great Falls

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 Great Falls

You may be interested in your other planting guides for Great Falls.