One of the best tools that you have as gardeners to help us determine 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.

In Calhoun you can figure out when it's a good idea to plant penstemon by referring to the USDA zone info.

Planting Calendar for Penstemon

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

You can plant penstemon just a bit earlier in the year because they do well in moderate cold.

The earliest that you can plant penstemon in Calhoun 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. If you wait any later than that and your penstemon may not have a chance to grow to maturity. If you are starting your penstemon indoors then you might be able to get away with starting them a little bit earlier.

Last Frost Date

In Calhoun the average date of last frost happens on April 15. It might get as low as 5°F during the coldest months of winter.

Since the USDA zone info for Calhoun is an average the actual date of last frost is different every year. Half of the time in Calhoun you get a frost after April 15 so be sure to be ready to cover your penstemon in the event of a late frost.

USDA Zone Info for Calhoun

Here is the info for USDA Zone 7b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	5°F
Highest Expected Low	10°F

This means that on a really cold year, the coldest it will get is 5°F. On most years you should be prepared to experience lows near 10°F.

Plants to Grow in Calhoun

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