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.

By referring to the USDA zone info for Gillette you will be able to figure out when it's possible to plant penstemon.

Planting Calendar for Penstemon

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

Since penstemon are one of those plants that can tolerate a little bit of cold weather you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant penstemon in Gillette 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 penstemon and expect a good harvest is probably August. Any later than that and your penstemon may not have a chance to really do well. You can get started a little bit earlier by starting your penstemon indoors.

Last Frost Date

In Gillette the average date of last frost happens on May 15. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Gillette may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Since half of the time in Gillette it frosts late in the year after May 15 be ready to cover your penstemon in the event of a surprise late frost.

USDA Zone Info for Gillette

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 Gillette

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