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

By looking at the USDA zone info for Billings it's possible to estimate when it's the best time to plant cardinal flower.

Planting Calendar for Cardinal Flower

Frost tolerance for cardinal flower:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Cardinal Flower require warm weather which means that you have to wait until it warms up after the last frost when the weather gets warmer before you can plant them.

The earliest that you can plant cardinal flower in Billings is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant cardinal flower and expect a good harvest is probably August. You probably don't want to wait any later than that or else your cardinal flower may not have a chance to really do well. Starting your cardinal flower indoors is a great way to get them started a few weeks earlier.

Last Frost Date

On average the last frost is on May 15 in Billings. You can expect an average low temperature of -25°F in the coldest months of winter.

Since the USDA zone info for Billings may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Billings it frosts late in the year after May 15 so be sure to be ready to cover your cardinal flower if you have a late frost.

USDA Zone Info for Billings

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 Billings

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