The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can figure out when it's a good idea to plant snapdragons in Helena by looking at the USDA zone info.

Planting Calendar for Snapdragons

Frost tolerance for snapdragons:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant snapdragons a little earlier in the year because they do well in moderate cold.

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

The last month that you can plant snapdragons and expect a good harvest is probably August. If you wait any later than that and your snapdragons may not have a chance to really do well. Starting your snapdragons indoors is a great way to get them started 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 just an average the actual date of last frost changes from year to year. Half of the time in Helena last frost occurs after May 15 so be sure to be ready to cover your snapdragons if you have 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.