One of the first steps you take when you are getting a good idea 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.

In Bismarck you can estimate when to plant echinacea by reviewing the USDA zone info.

Planting Calendar for Echinacea

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

Echinacea are barely cold tolerant which means that you can plant them slightly earlier than other frost tender plants.

The earliest that you can plant echinacea in Bismarck 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 echinacea and expect a good harvest is probably August. If you wait any later than that and your echinacea may not have a chance to fully mature. If you are starting your echinacea indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Since the USDA zone info for Bismarck is just an average the actual date of last frost changes from year to year. Since half of the time in Bismarck there is a last frost after May 15 be ready to cover your echinacea in the event of a late frost.

USDA Zone Info for Bismarck

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 Bismarck

You may be interested in your other planting guides for Bismarck.