The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can estimate when it's possible to plant scallions in San Francisco by checking out the USDA zone info.

Planting Calendar for Scallions

Frost tolerance for scallions:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Scallions can survive in some cold which tells us that you can plant them slightly earlier in the year than other frost tender plants.

The earliest that you can plant scallions 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 scallions and expect a good harvest is probably September. Any later than that and your scallions may not have a chance to really do well. You can get started a few weeks earlier by starting your scallions indoors.

Last Frost Date

The average date of last frost is 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 not always accurate the actual date of last frost changes from year to year. Since half of the time in San Francisco there is a last frost after January 31 be ready to protect your scallions 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.