The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when you can plant dahlias in Bismarck by checking out the USDA zone info.

Planting Calendar for Dahlias

Frost tolerance for dahlias:	Not tolerant of frost.
When to plant:	After the last frost has passed.

Dahlias are not cold tolerant which means that it is necessary to wait until it warms up after the last frost has passed before you can plant them.

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

Last Frost Date

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

Since the USDA zone info for Bismarck is an average the actual date of last frost can change quite a bit from year to year. Half of the time in Bismarck there is a last frost after May 15 so be sure to be ready to protect your dahlias if you have a surprise 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.