One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Laurel you can determine when it's the best time to plant thunbergia 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 when the weather gets warmer.

Thunbergia require warm weather which tells us that it is important to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant thunbergia in Laurel 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. Any later than that and 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 little bit earlier.

Last Frost Date

In Laurel the average date of last frost happens on May 15. You can expect an average low temperature of -25°F in the coldest months of winter.

Remember that USDA zone info for Laurel may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Laurel there is a last frost after May 15 be ready to cover your thunbergia if you have a surprise late frost.

USDA Zone Info for Laurel

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 Laurel

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