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

It's possible to estimate when it's possible to plant thunbergia by looking at the USDA zone info for Mount Vernon.

Planting Calendar for Thunbergia

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

It's probably not a good idea to plant thunbergia until after the last frost because they do not do well in cold weather.

The earliest that you can plant thunbergia in Mount Vernon 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. You probably don't want to wait any later than that or else your thunbergia may not have a chance to fully mature. Starting your thunbergia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Mount Vernon the average date of last frost happens on April 15. You should expect an average low temperature of -10°F in the coldest months of winter.

Always keep in mind that USDA zone info for Mount Vernon may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Mount Vernon it frosts late in the year after April 15 so be sure to be ready to cover your thunbergia in the event of a late frost.

USDA Zone Info for Mount Vernon

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 Mount Vernon

You may be interested in your other planting guides for Mount Vernon.