One of the first steps you take when you are figuring out your gardening schedule is find your 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.

In San Diego you can estimate when you can plant thunbergia by checking out the USDA zone info.

Planting Calendar for Thunbergia

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

Since thunbergia do not do well in cold weather it's necessary to wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant thunbergia in San Diego is February. However, you really should wait until March 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 grow to maturity. You can get started a couple of weeks earlier by starting your thunbergia indoors.

Last Frost Date

In San Diego the average date of last frost happens on January 31. You can expect an average low temperature of 35°F in the coldest months of winter.

Since the USDA zone info for San Diego is an average the actual date of last frost changes from year to year. Since half of the time in San Diego you get a frost after January 31 be ready to cover your thunbergia if you have a surprise late frost.

USDA Zone Info for San Diego

Here is the info for USDA Zone 10b.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	35°F
Highest Expected Low	40°F

This means that on a really cold year, the coldest it will get is 35°F. On most years you should be prepared to experience lows near 40°F.

Plants to Grow in San Diego

You may be interested in your other planting guides for San Diego.