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.

You will be able to estimate when it's a good idea to plant balsam by referring to the USDA zone info for Helena.

Planting Calendar for Balsam

Frost tolerance for balsam:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

You should not plant balsam until after the last frost has passed because they require warm weather.

The earliest that you can plant balsam in Helena is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant balsam and expect a good harvest is probably August. Any later than that and your balsam may not have a chance to fully mature. If you are starting your balsam indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on May 15 in Helena. You should expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Helena is an average the actual date of last frost is different every year. Since half of the time in Helena last frost occurs after May 15 be ready to protect your balsam in the event of a late frost.

USDA Zone Info for Helena

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Helena

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