The USDA Zone info is a great tool for gardeners to help us figure out 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 it's possible to plant torenia in Mandan by reviewing the USDA zone info.

Planting Calendar for Torenia

Frost tolerance for torenia:	Not tolerant of frost.
When to plant:	After the last frost.

Since torenia do not do well in cold weather it's necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant torenia 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 torenia and expect a good harvest is probably August. Any later than that and your torenia may not have a chance to fully mature. You can get started a few weeks earlier by starting your torenia indoors.

Last Frost Date

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

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Mandan and it will vary from year to year. Since half of the time in Mandan you get a frost after May 15 be ready to cover your torenia in the event of a 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.