Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Evansville can be reffered to in order to determine when it's a good idea to plant thunbergia.

Planting Calendar for Thunbergia

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

Since thunbergia are not cold tolerant it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant thunbergia in Evansville 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 fully mature. If you are starting your thunbergia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Evansville. You should expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Evansville is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Evansville it frosts late in the year after April 15 so be sure to be ready to protect your thunbergia if you have one of those late frosts.

USDA Zone Info for Evansville

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Evansville

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