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

The earliest that you can plant thunbergia in East Grand Forks 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 the last frost.

You should not plant thunbergia until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant thunbergia in East Grand Forks is May. However, you really should wait until June 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 really do well. 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

The average date of last frost is May 15 in East Grand Forks. It might get as low as -30°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for East Grand Forks and it changes from year to year. Since half of the time in East Grand Forks you get a frost after May 15 be ready to cover your thunbergia in the event of a surprise late frost.

USDA Zone Info for East Grand Forks

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in East Grand Forks

You may be interested in your other planting guides for East Grand Forks.