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.

The best time to plant runner beans in Baltimore should be determined by referring to 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.

It's a bad idea to plant runner beans until after the last frost because they do not do well in cold weather.

The earliest that you can plant runner beans in Baltimore 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 runner beans and expect a good harvest is probably August. 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

In Baltimore the average date of last frost happens on April 15. You can expect an average low temperature of 5°F in the coldest months of winter.

Since the USDA zone info for Baltimore is just an average the actual date of last frost will vary from year to year. Half of the time in Baltimore you get surprised by a frost after April 15 so just be sure to be ready to cover your runner beans in the event of a surprise late frost.

USDA Zone Info for Baltimore

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Baltimore

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