One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. 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 Indiana should be looked at to determine when it's the best time to plant thunbergia.

Planting Calendar for Thunbergia

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

You can not plant thunbergia until after all chance of frost has passed because they are not cold tolerant.

The earliest that you can plant thunbergia in Indiana 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. Starting your thunbergia indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is April 15 in Indiana. It might get as low as -10°F during the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Indiana and it will vary from year to year. Since half of the time in Indiana you get a frost after April 15 be ready to protect your thunbergia in the event of one of those late frosts.

USDA Zone Info for Indiana

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Indiana

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