Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The best time to plant alstromeria in San Francisco can be determined by checking out the USDA zone info.

Planting Calendar for Alstromeria

Frost tolerance for alstromeria:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant alstromeria a bit earlier in the year because they are one of those plants that can tolerate a little bit of cold weather.

The earliest that you can plant alstromeria in San Francisco is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant alstromeria and expect a good harvest is probably October. If you wait any later than that and your alstromeria may not have a chance to fully mature. You can get started a few weeks earlier by starting your alstromeria indoors.

Last Frost Date

The average date of last frost is January 31 in San Francisco. You can expect an average low temperature of 35°F in the coldest months of winter.

Since the USDA zone info for San Francisco is just an average the actual date of last frost will vary from year to year. Half of the time in San Francisco there is a last frost after January 31 so make sure that you are prepared to cover your alstromeria 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.