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.

By looking at the USDA zone info for Coos Bay it's a good idea to estimate when to plant thunbergia.

Planting Calendar for Thunbergia

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

Since thunbergia require warm weather it is important to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant thunbergia in Coos Bay 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 fully mature. If you are starting your thunbergia indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on February 15 in Coos Bay. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Coos Bay is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Coos Bay there is a last frost after February 15 so make sure that you are prepared to protect your thunbergia in the event of a surprise late frost.

USDA Zone Info for Coos Bay

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 Coos Bay

You may be interested in your other planting guides for Coos Bay.