One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for San Francisco should be used to estimate when it's a good idea to plant lisianthus.

Planting Calendar for Lisianthus

Frost tolerance for lisianthus:	Not tolerant of frost.
When to plant:	After the last frost.

Lisianthus require warm weather which tells us that you need to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant lisianthus 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 lisianthus and expect a good harvest is probably September. If you wait any later than that and your lisianthus may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your lisianthus indoors.

Last Frost Date

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

Keep in mind that USDA zone info for San Francisco is an average and the actual date of last frost changes 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 lisianthus in the event of one of those late frosts.

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.