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

You will be able to figure out when it's the best time to plant thunbergia by looking at the USDA zone info for Greendale.

Planting Calendar for Thunbergia

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

It's not a good idea to plant thunbergia until after all chance of frost has passed because they do not do well in cold weather.

The earliest that you can plant thunbergia in Greendale 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 grow to maturity. Starting your thunbergia indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost is on April 15 in Greendale. In the coldest months of winter you should expect an average low temperature of -15°F.

It's important to remember that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Greendale and it changes from year to year. Half of the time in Greendale last frost occurs after April 15 so always be ready to cover your thunbergia in the event of a late frost.

USDA Zone Info for Greendale

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Greendale

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