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When to Plant String beans in San Francisco, CA

One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when to plant string beans in San Francisco by referring to the USDA zone info.


Planting Calendar for String beans

Frost tolerance for string beans: Not tolerant of frost.
When to plant: After the last frost when the weather gets warmer.

String beans are not cold tolerant which means that it is necessary to wait until it warms up after the last frost before you can plant them.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant string beans
Possibly ok, but a risky time to plant string beans
Probably not a good time to plant string beans

The earliest that you can plant string beans 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 string beans and expect a good harvest is probably September. You probably don't want to wait any later than that or else your string beans may not have a chance to really do well. You can get started a few weeks earlier by starting your string beans indoors.

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.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for San Francisco and it will vary from year to year. Half of the time in San Francisco you get a frost after January 31 so always be ready to cover your string beans if you have 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 Low35°F
Highest Expected Low40°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.