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 earliest that you can plant mustard in San Francisco can be estimated by checking out the USDA zone info.

Planting Calendar for Mustard

Frost tolerance for mustard:	Not tolerant of frost.
When to plant:	After the last frost has passed.

It's probably not a good idea to plant mustard until after the last frost because they require warm weather.

The earliest that you can plant mustard 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 mustard and expect a good harvest is probably September. You probably don't want to wait any later than that or else your mustard may not have a chance to really do well. If you are starting your mustard indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on January 31 in San Francisco. It might get as low as 35°F during the coldest months of winter.

Keep in mind that the actual date of last frost is just an average because it is based on the USDA zone info for San Francisco and it is different every year. Half of the time in San Francisco it frosts late in the year after January 31 so make sure that you are prepared to cover your mustard 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.