The USDA Zone info is a great tool for gardeners to help us determine 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.

By checking out the USDA zone info for Helena you should be able to determine when it's a good idea to plant heuchera.

Planting Calendar for Heuchera

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

Heuchera are one of those plants that can tolerate a little bit of cold weather which means that you can get them planted earlier than other frost tender plants.

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

Last Frost Date

In Helena the average date of last frost happens on May 15. It might get as low as -25°F during 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 you get surprised by a frost after May 15 be ready to cover your heuchera if you have one of those late frosts.

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.