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.

By checking out the USDA zone info for Massena you should be able to figure out when it's the best time to plant thunbergia.

Planting Calendar for Thunbergia

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

Since thunbergia require warm weather it's important to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant thunbergia in Massena 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 really do well. You can get started a little bit earlier by starting your thunbergia indoors.

Last Frost Date

The average date of last frost is May 15 in Massena. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Massena is an average the actual date of last frost will vary from year to year. Half of the time in Massena it frosts late in the year after May 15 so make sure that you are ready to cover your thunbergia in the event of a late frost.

USDA Zone Info for Massena

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Massena

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