One of the first steps you take when you are estimating 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.

The USDA zone info for Mill Valley should be reviewed to estimate when it's the best time to plant runner beans.

Planting Calendar for Runner beans

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

Runner beans are not cold tolerant which means that it is necessary to wait until it warms up after all chance of frost has passed before you can plant them.

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

Last Frost Date

In Mill Valley the average date of last frost happens on January 31. You should expect an average low temperature of 30°F in the coldest months of winter.

It's important to remember that USDA zone info for Mill Valley is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Mill Valley it frosts late in the year after January 31 be ready to cover your runner beans if you have a surprise late frost.

USDA Zone Info for Mill Valley

Here is the info for USDA Zone 10a.

Average Date of Last Frost (spring)	January 31
Average Date of First Frost (fall)	December 15
Lowest Expected Low	30°F
Highest Expected Low	35°F

This means that on a really cold year, the coldest it will get is 30°F. On most years you should be prepared to experience lows near 35°F.

Plants to Grow in Mill Valley

You may be interested in your other planting guides for Mill Valley.