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.

You should be able to estimate when you can plant thunbergia by looking at the USDA zone info for Humble.

Planting Calendar for Thunbergia

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

You should not plant thunbergia until after the last frost when the weather gets warmer because they are not cold tolerant.

The earliest that you can plant thunbergia in Humble is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant thunbergia and expect a good harvest is probably September. If you wait any later than that and your thunbergia may not have a chance to grow to maturity. Starting your thunbergia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Humble. In the coldest months of winter you can expect an average low temperature of 20°F.

Since the USDA zone info for Humble is just an average the actual date of last frost can change quite a bit from year to year. Since half of the time in Humble you get surprised by a frost after February 15 be ready to protect your thunbergia in the event of a surprise late frost.

USDA Zone Info for Humble

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

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

Plants to Grow in Humble

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