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 earliest that you can plant monarda in Great Falls should be estimated by referring to the USDA zone info.

Planting Calendar for Monarda

Frost tolerance for monarda:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since monarda do ok in moderate cold you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant monarda in Great Falls is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant monarda and expect a good harvest is probably August. You probably don't want to wait any later than that or else your monarda may not have a chance to really do well. If you are starting your monarda indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Great Falls is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Great Falls last frost occurs after May 15 so make sure that you are ready to protect your monarda 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.