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

The first opportunity to plant thunbergia in Salem should be figured out by using the USDA zone info.

Planting Calendar for Thunbergia

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

Since thunbergia are not cold tolerant you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant thunbergia in Salem 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. 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 April 15 in Salem. It might get as low as -5°F during the coldest months of winter.

Remember that USDA zone info for Salem is not always accurate and the actual date of last frost will vary from year to year. Half of the time in Salem you get a 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 Salem

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 Salem

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