The USDA Zone info is a great tool for gardeners to help us determine your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You can figure out when you can plant lunaria in Helena by using the USDA zone info.

Planting Calendar for Lunaria

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

Lunaria do ok in some cold which means that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant lunaria 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 lunaria and expect a good harvest is probably August. Any later than that and your lunaria may not have a chance to fully mature. You can get started a little bit earlier by starting your lunaria 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.

Keep in mind that USDA zone info for Helena is just an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Helena you get surprised by a frost after May 15 so always be ready to cover your lunaria in the event of 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.