One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of figuring out when it's a good idea to plant scarlet runner beans is to consult the USDA zone info for San Diego.

Planting Calendar for Scarlet Runner Beans

Frost tolerance for scarlet runner beans:	Not tolerant of frost.
When to plant:	After the last frost.

Scarlet Runner Beans require warm weather which tells us that you need to wait until it warms up after the last frost has passed before you can plant them.

The earliest that you can plant scarlet runner beans in San Diego 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 scarlet runner beans and expect a good harvest is probably September. If you wait any later than that and your scarlet runner beans may not have a chance to fully mature. Starting your scarlet runner beans indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

The average date of last frost is January 31 in San Diego. It might get as low as 35°F during the coldest months of winter.

Since the USDA zone info for San Diego may not be accurate from year to year the actual date of last frost changes from year to year. Since half of the time in San Diego it frosts late in the year after January 31 be ready to cover your scarlet runner beans in the event of one of those late frosts.

USDA Zone Info for San Diego

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 Diego

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