One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Helena should be looked at to determine when it's a good idea to plant flowering kale.

Planting Calendar for Flowering Kale

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

Flowering Kale are moderately cold tolerant which means that you can plant them earlier than more sensitive plants.

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

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

Last Frost Date

On average the last frost has passed is on March 15 in Helena. It might get as low as 10°F during the coldest months of winter.

Always keep in mind that the actual date of last frost is not always accurate because it is based on the USDA zone info for Helena and it changes from year to year. Since half of the time in Helena you get surprised by a frost after March 15 be ready to cover your flowering kale if you have a surprise late frost.

USDA Zone Info for Helena

Here is the info for USDA Zone 8a.

Average Date of Last Frost (spring)	March 15
Average Date of First Frost (fall)	November 15
Lowest Expected Low	10°F
Highest Expected Low	15°F

This means that on a really cold year, the coldest it will get is 10°F. On most years you should be prepared to experience lows near 15°F.

Plants to Grow in Helena

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