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.

The USDA zone info for Franklin should be reviewed to estimate when you can plant penstemon.

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 a bit earlier in the year because they are moderately cold tolerant.

The earliest that you can plant penstemon in Franklin 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. You probably don't want to wait any later than that or else your penstemon may not have a chance to grow to maturity. You can get started a couple of weeks earlier by starting your penstemon indoors.

Last Frost Date

On average the last frost is on April 15 in Franklin. It might get as low as -20°F during the coldest months of winter.

Keep in mind that the actual date of last frost is an average because it is based on the USDA zone info for Franklin and it changes from year to year. Since half of the time in Franklin you get surprised by a frost after April 15 be ready to protect your penstemon if you have a surprise late frost.

USDA Zone Info for Franklin

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Franklin

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