One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. 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 Roseburg should be estimated by referring to the USDA zone info.

Planting Calendar for Thunbergia

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

It's probably not a good idea to plant thunbergia until after the last frost has passed because they do not do well in cold weather.

The earliest that you can plant thunbergia in Roseburg 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. Any later than that and your thunbergia may not have a chance to really do well. Starting your thunbergia indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on February 15 in Roseburg. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Roseburg is an average the actual date of last frost is different every year. Since half of the time in Roseburg you get surprised by a frost after February 15 be ready to protect your thunbergia if you have a surprise late frost.

USDA Zone Info for Roseburg

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 Roseburg

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