One of the best tools that you have as gardeners to help us determine your gardening schedule is the 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.

By looking at the USDA zone info for Park Forest it's possible 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.

It's not a good idea to plant thunbergia until after all chance of frost has passed because they require warm weather.

The earliest that you can plant thunbergia in Park Forest 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. If you wait any later than that and your thunbergia may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your thunbergia indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Park Forest. You should expect an average low temperature of -15°F in the coldest months of winter.

Remember that USDA zone info for Park Forest may not be accurate from year to year and the actual date of last frost will vary from year to year. Half of the time in Park Forest it frosts late in the year after April 15 so make sure that you are prepared to cover your thunbergia in the event of one of those late frosts.

USDA Zone Info for Park Forest

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 Park Forest

You may be interested in your other planting guides for Park Forest.