Before planting it is a good idea to find your USDA Zone info to figure out 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 reviewing the USDA zone info for Waterloo it's a good idea to estimate when it's possible to plant string beans.

Planting Calendar for String beans

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

Since string beans require warm weather it's necessary to wait until after the last frost before you can plant them.

The earliest that you can plant string beans in Waterloo 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 really do well. Starting your string beans indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Waterloo. You should expect an average low temperature of -10°F in the coldest months of winter.

It's important to remember that USDA zone info for Waterloo is just an average and the actual date of last frost can change quite a bit from year to year. Since half of the time in Waterloo you get surprised by a frost after April 15 be ready to protect your string beans in the event of one of those late frosts.

USDA Zone Info for Waterloo

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 Waterloo

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