Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

By looking at the USDA zone info for Bowling Green you should be able to determine 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.

Penstemon do well in some cold which means that you can plant them a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant penstemon in Bowling Green 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. 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 Bowling Green the average date of last frost happens on April 15. You should expect an average low temperature of -5°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Bowling Green and it will vary from year to year. Since half of the time in Bowling Green it frosts late in the year after April 15 be ready to cover your penstemon in the event of a late frost.

USDA Zone Info for Bowling Green

Here is the info for USDA Zone 6b.

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

Plants to Grow in Bowling Green

You may be interested in your other planting guides for Bowling Green.