One of the best tools that you have as gardeners to help us estimate 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.

The first chance to plant thunbergia in Mount Vernon should be determined by looking at 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.

It's a bad idea to plant thunbergia until after the last frost because they require warm 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 grow to maturity. You can get started a little bit earlier by starting your thunbergia indoors.

Last Frost Date

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

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Mount Vernon and it can change quite a bit from year to year. Since half of the time in Mount Vernon you get surprised by a frost after April 15 be ready to cover your thunbergia if you have one of those late frosts.

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.