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.

By looking at the USDA zone info for Billings you will be able to figure out when it's the best time to plant foxglove.

Planting Calendar for Foxglove

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

Since foxglove do well in moderate cold you can plant them a bit earlier in the year than plants that are more sensitive to the cold.

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

Last Frost Date

On average the last frost is on May 15 in Billings. It might get as low as -25°F during 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 is different every year. Since half of the time in Billings there is a last frost after May 15 be ready to cover your foxglove in the event of a surprise 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.