One of the first steps you take when you are getting a good idea your gardening schedule is find your 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.

You can determine when it's possible to plant penstemon in Cincinnati by using 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 Cincinnati 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 fully mature. If you are starting your penstemon indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Cincinnati. In the coldest months of winter you can expect an average low temperature of -5°F.

Keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Cincinnati and it is different every year. Half of the time in Cincinnati you get surprised by a frost after April 15 so always be ready to cover your penstemon if you have one of those late frosts.

USDA Zone Info for Cincinnati

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 Cincinnati

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