One of the best tools that you have as gardeners to help us figure out your gardening schedule is the 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.

It's possible to estimate when to plant green beans by looking at the USDA zone info for Helena.

Planting Calendar for Green beans

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

Since green beans do not do well in cold weather it is necessary to wait until after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant green beans in Helena 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 green beans and expect a good harvest is probably August. Any later than that and your green beans may not have a chance to really do well. If you are starting your green beans indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost is on March 15 in Helena. You should expect an average low temperature of 10°F in the coldest months of winter.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Helena and it is different every year. Since half of the time in Helena there is a last frost after March 15 be ready to cover your green beans if you have one of those late frosts.

USDA Zone Info for Helena

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 Helena

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