One of the best tools that you have as gardeners to help us estimate 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.

In Carterville you can estimate when it's the best time to plant thunbergia by referring to the USDA zone info.

Planting Calendar for Thunbergia

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

Since thunbergia do not do well in cold weather you have to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant thunbergia in Carterville is April. However, you really should wait until May if you don't want to take any chances.

The last month that you can plant thunbergia and expect a good harvest is probably August. Any later than that and your thunbergia may not have a chance to really do well. You can get started a few weeks earlier by starting your thunbergia indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Carterville. In the coldest months of winter you can expect an average low temperature of -5°F.

Keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Carterville and it is different every year. Half of the time in Carterville it frosts late in the year after April 15 so just be sure to be ready to cover your thunbergia if you have a late frost.

USDA Zone Info for Carterville

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Carterville

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