One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. 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 string beans in Portsmouth should be determined by looking at the USDA zone info.

Planting Calendar for String beans

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

It's probably not a good idea to plant string beans until after the last frost because they require warm weather.

The earliest that you can plant string beans in Portsmouth 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. Any later than that and your string beans may not have a chance to grow to maturity. If you are starting your string beans indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

In Portsmouth the average date of last frost happens on April 15. In the coldest months of winter you can expect an average low temperature of -10°F.

Keep in mind that USDA zone info for Portsmouth is just an average and the actual date of last frost changes from year to year. Half of the time in Portsmouth you get a frost after April 15 so always be ready to protect your string beans in the event of one of those late frosts.

USDA Zone Info for Portsmouth

Here is the info for USDA Zone 6a.

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

Plants to Grow in Portsmouth

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