One of the first steps you take when you are figuring out your gardening schedule is find your 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.

By using the USDA zone info for Great Falls you should be able to estimate when it's possible to plant cuphea.

Planting Calendar for Cuphea

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

Since cuphea do not do well in cold weather you really should wait until after the last frost before you can plant them.

The earliest that you can plant cuphea 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 cuphea and expect a good harvest is probably August. If you wait any later than that and your cuphea may not have a chance to really do well. You can get started a little bit earlier by starting your cuphea indoors.

Last Frost Date

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

Since the USDA zone info for Great Falls is an average the actual date of last frost will vary from year to year. Half of the time in Great Falls you get surprised by a frost after May 15 so make sure that you are prepared to protect your cuphea if you have a 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.