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.

In Billings you can determine when you can plant scarlet pimpernels by checking out the USDA zone info.

Planting Calendar for Scarlet Pimpernels

Frost tolerance for scarlet pimpernels:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Since scarlet pimpernels do ok in moderate cold you can plant them just a tiny bit earlier in the year than other frost tender plants.

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

The last month that you can plant scarlet pimpernels and expect a good harvest is probably August. If you wait any later than that and your scarlet pimpernels may not have a chance to grow to maturity. If you are starting your scarlet pimpernels indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

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

Remember that USDA zone info for Billings is not always accurate and the actual date of last frost is different every year. Since half of the time in Billings last frost occurs after May 15 be ready to cover your scarlet pimpernels if you have one of those late frosts.

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.