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.

By reviewing the USDA zone info for South San Francisco you should be able to estimate when it's a good idea to plant calla lily.

Planting Calendar for Calla Lily

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

Since calla lily are not cold tolerant it's necessary to wait until after the last frost has passed before you can plant them.

The earliest that you can plant calla lily in South 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 calla lily and expect a good harvest is probably September. If you wait any later than that and your calla lily may not have a chance to fully mature. You can get started a little bit earlier by starting your calla lily indoors.

Last Frost Date

The average date of last frost is January 31 in South San Francisco. It might get as low as 30°F during the coldest months of winter.

Since the USDA zone info for South San Francisco is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in South San Francisco you get surprised by a frost after January 31 so just be sure to be ready to cover your calla lily if you have a late frost.

USDA Zone Info for South San Francisco

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in South San Francisco

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