One of the first steps you take when you are figuring out your gardening schedule is find your 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.

You can figure out when it's possible to plant thunbergia in Mound by reviewing 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.

It's probably a bad idea to plant thunbergia until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant thunbergia in Mound 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 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 the last frost has passed is on May 15 in Mound. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Mound may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Mound last frost occurs after May 15 so be sure to be ready to cover your thunbergia if you have a surprise late frost.

USDA Zone Info for Mound

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 Mound

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