The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Round Lake you can figure out when you can 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 all chance of frost has passed.

Thunbergia do not do well in cold weather which means that you must wait until it warms up after the last frost before you can plant them.

The earliest that you can plant thunbergia in Round Lake 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 Round Lake. You should expect an average low temperature of -15°F in the coldest months of winter.

Always keep in mind that USDA zone info for Round Lake is an average and the actual date of last frost changes from year to year. Since half of the time in Round Lake you get a frost after April 15 be ready to cover your thunbergia if you have a late frost.

USDA Zone Info for Round Lake

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 Round Lake

You may be interested in your other planting guides for Round Lake.