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.

In Mandan you can figure out when it's possible to plant blue throatwort by checking out the USDA zone info.

Planting Calendar for Blue Throatwort

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

Since blue throatwort are not cold tolerant it is important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant blue throatwort in Mandan 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 blue throatwort and expect a good harvest is probably August. If you wait any later than that and your blue throatwort may not have a chance to grow to maturity. Starting your blue throatwort indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is May 15 in Mandan. It might get as low as -30°F during 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 Mandan and it changes from year to year. Half of the time in Mandan you get surprised by a frost after May 15 so be sure to be ready to cover your blue throatwort if you have a surprise late frost.

USDA Zone Info for Mandan

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 Mandan

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