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 checking out the USDA zone info for San Francisco it's possible to estimate when it's a good idea to plant trachelium.

Planting Calendar for Trachelium

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

You really shouldn't plant trachelium until after the last frost because they require warm weather.

The earliest that you can plant trachelium in San Francisco 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 trachelium and expect a good harvest is probably September. Any later than that and your trachelium may not have a chance to really do well. If you are starting your trachelium indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

On average the last frost has passed is on January 31 in San Francisco. In the coldest months of winter you can expect an average low temperature of 35°F.

Since the USDA zone info for San Francisco is an average the actual date of last frost will vary from year to year. Since half of the time in San Francisco it frosts late in the year after January 31 be ready to cover your trachelium if you have a surprise late frost.

USDA Zone Info for San Francisco

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 Francisco

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