One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

The best time to plant torenia in Pierre can be figured out by looking at the USDA zone info.

Planting Calendar for Torenia

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

Since torenia do not do well in cold weather you need 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 Pierre 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. You probably don't want to wait any later than that or else your torenia may not have a chance to grow to maturity. If you are starting your torenia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Pierre. You can expect an average low temperature of -25°F in the coldest months of winter.

Keep in mind that USDA zone info for Pierre is just an average and the actual date of last frost is different every year. Since half of the time in Pierre you get surprised by a frost after May 15 be ready to cover your torenia in the event of one of those late frosts.

USDA Zone Info for Pierre

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Pierre

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