One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By reviewing the USDA zone info for Duvall you will be able to figure out when you can plant thunbergia.

Planting Calendar for Thunbergia

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

It's a bad idea to 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 Duvall 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 fully mature. You can get started a couple of weeks earlier by starting your thunbergia indoors.

Last Frost Date

In Duvall the average date of last frost happens on March 15. In the coldest months of winter you should expect an average low temperature of 15°F.

Remember that USDA zone info for Duvall is just an average and the actual date of last frost will vary from year to year. Half of the time in Duvall you get a frost after March 15 so make sure that you are ready to protect your thunbergia if you have one of those late frosts.

USDA Zone Info for Duvall

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Duvall

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