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.

It's possible to estimate when you can plant doronicum by looking at the USDA zone info for Great Falls.

Planting Calendar for Doronicum

Frost tolerance for doronicum:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

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

The earliest that you can plant doronicum in Great Falls 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 doronicum and expect a good harvest is probably August. Any later than that and your doronicum may not have a chance to fully mature. If you are starting your doronicum indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

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

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Great Falls and it changes from year to year. Since half of the time in Great Falls you get surprised by a frost after May 15 be ready to protect your doronicum if you have one of those late frosts.

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.