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.

A way of making a decision about when it's the best time to plant torenia is to examine the USDA zone info for Lewistown.

Planting Calendar for Torenia

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

You can not plant torenia until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant torenia in Lewistown 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 really do well. Starting your torenia indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Lewistown. You can expect an average low temperature of -30°F in the coldest months of winter.

Remember that USDA zone info for Lewistown is not always accurate and the actual date of last frost can change quite a bit from year to year. Half of the time in Lewistown you get a frost after May 15 so be sure to be ready to protect your torenia if you have a late frost.

USDA Zone Info for Lewistown

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 Lewistown

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