Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

By checking out the USDA zone info for Philadelphia it's possible to estimate when it's a good idea to plant string beans.

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.

Since string beans do not do well in cold weather you really should wait until after all chance of frost has passed before you can plant them.

The earliest that you can plant string beans in Philadelphia 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. If you wait any later than that and your string beans may not have a chance to really do well. If you are starting your string beans indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

The average date of last frost is March 15 in Philadelphia. You can expect an average low temperature of 10°F in the coldest months of winter.

Remember that USDA zone info for Philadelphia is an average and the actual date of last frost is different every year. Since half of the time in Philadelphia there is a last frost after March 15 be ready to protect your string beans if you have one of those late frosts.

USDA Zone Info for Philadelphia

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Philadelphia

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