One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of getting a good idea when it's the best time to plant penstemon is to look at the USDA zone info for Riverton.

Planting Calendar for Penstemon

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

Penstemon do well in moderate cold which tells us that you can plant them earlier than other plants that might not handle the cold.

The earliest that you can plant penstemon in Riverton 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 penstemon and expect a good harvest is probably September. Any later than that and your penstemon may not have a chance to fully mature. You can get started a few weeks earlier by starting your penstemon indoors.

Last Frost Date

In Riverton the average date of last frost happens on April 15. You can expect an average low temperature of 0°F in the coldest months of winter.

Always keep in mind that USDA zone info for Riverton is just an average and the actual date of last frost changes from year to year. Since half of the time in Riverton you get surprised by a frost after April 15 be ready to protect your penstemon in the event of a late frost.

USDA Zone Info for Riverton

Here is the info for USDA Zone 7a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	0°F
Highest Expected Low	5°F

This means that on a really cold year, the coldest it will get is 0°F. On most years you should be prepared to experience lows near 5°F.

Plants to Grow in Riverton

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