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.

The earliest that you can plant forget-me-not in Helena can be determined by referring to the USDA zone info.

Planting Calendar for Forget-Me-Not

Frost tolerance for forget-me-not:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

Forget-Me-Not are moderately cold tolerant which tells us that you can plant them earlier than more sensitive plants.

The earliest that you can plant forget-me-not 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 forget-me-not and expect a good harvest is probably August. If you wait any later than that and your forget-me-not may not have a chance to fully mature. You can get started a little bit earlier by starting your forget-me-not indoors.

Last Frost Date

The average date of last frost is May 15 in Helena. It might get as low as -25°F during the coldest months of winter.

Always keep in mind that USDA zone info for Helena is an average and the actual date of last frost is different every year. Half of the time in Helena you get a frost after May 15 so make sure that you are prepared to protect your forget-me-not 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.