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

The first chance to plant thunbergia in Chelsea can 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 the last frost has passed.

It's probably a bad idea to plant thunbergia until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant thunbergia in Chelsea 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. If you are starting your thunbergia indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Chelsea. In the coldest months of winter you should expect an average low temperature of -5°F.

It's important to remember that USDA zone info for Chelsea is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Chelsea there is a last frost after April 15 so just be sure to be ready to cover your thunbergia in the event of a surprise late frost.

USDA Zone Info for Chelsea

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Chelsea

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