When can I plant Thunbergia in Zone 3b

One of the first steps we take when we are estimating our gardening schedule is find our USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for our area.

It's possible to figure out when it's possible to plant thunbergia by looking at the USDA zone info for Zone 3b.


Planting Calendar for Thunbergia

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

Thunbergia require warm weather which tells us that it's important to wait until it warms up after all chance of frost has passed before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant thunbergia
Possibly ok, but a risky time to plant thunbergia
Probably not a good time to plant thunbergia

The earliest that you can plant thunbergia in Zone 3b 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. If you wait any later than that and your thunbergia may not have a chance to grow to maturity. If you are starting your thunbergia indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Zone 3b. We should expect an average low temperature of -35°F in the coldest months of winter.

It's important to remember that our actual date of last frost is not always accurate because it is based on the USDA zone info for Zone 3b and it is different every year. Half of the time in Zone 3b last frost occurs after May 15 so make sure that you are ready to cover your thunbergia if we have one of those late frosts.

USDA Zone Info for Zone 3b

Here is the info for USDA Zone 3b.

Average Date of Last Frost (spring)May 15
Average Date of First Frost (fall)September 15
Lowest Expected Low-35°F
Highest Expected Low-30°F

This means that on a really cold year, the coldest it will get is -35°F. On most years you should be prepared to experience lows near -30°F.

Plants to Grow in Zone 3b

You may be interested in our other planting guides for Zone 3b.