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.

A way of estimating when to plant string beans is to refer to the USDA zone info for Columbia.

Planting Calendar for String beans

Frost tolerance for string beans:	Not tolerant of frost.
When to plant:	After all chance of frost has passed.

String beans do not do well in cold weather which means that it is necessary to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant string beans in Columbia is April. However, you really should wait until May 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 August. You probably don't want to wait any later than that or else your string beans may not have a chance to grow to maturity. You can get started a few weeks earlier by starting your string beans indoors.

Last Frost Date

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

Since the USDA zone info for Columbia is not always accurate the actual date of last frost is different every year. Half of the time in Columbia last frost occurs after March 15 so make sure that you are prepared to protect your string beans in the event of a surprise late frost.

USDA Zone Info for Columbia

Here is the info for USDA Zone 8b.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	15°F
Highest Expected Low	20°F

This means that on a really cold year, the coldest it will get is 15°F. On most years you should be prepared to experience lows near 20°F.

Plants to Grow in Columbia

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