The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first chance to plant runner beans in Sonora can be figured out by reviewing the USDA zone info.

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 tells us that it's important to wait until it warms up after the last frost before you can plant them.

The earliest that you can plant runner beans in Sonora is March. However, you really should wait until April 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. Any later than that and your runner beans may not have a chance to grow to maturity. Starting your runner beans indoors is a great way to get them started a few weeks earlier.

Last Frost Date

The average date of last frost is February 15 in Sonora. You can expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Sonora may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Sonora there is a last frost after February 15 be ready to protect your runner beans in the event of a late frost.

USDA Zone Info for Sonora

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°F

This means that on a really cold year, the coldest it will get is 20°F. On most years you should be prepared to experience lows near 25°F.

Plants to Grow in Sonora

You may be interested in your other planting guides for Sonora.