One of the first steps you take when you are determining your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A common way of estimating when you can plant penstemon is to consult the USDA zone info for Calumet City.

Planting Calendar for Penstemon

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

Since penstemon do well in moderate cold you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant penstemon in Calumet City 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 really do well. You can get started a few weeks earlier by starting your penstemon indoors.

Last Frost Date

On average the last frost is on April 15 in Calumet City. You should expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Calumet City is just an average the actual date of last frost will vary from year to year. Half of the time in Calumet City last frost occurs after April 15 so make sure that you are ready to cover your penstemon if you have a surprise late frost.

USDA Zone Info for Calumet City

Here is the info for USDA Zone 6a.

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

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

Plants to Grow in Calumet City

You may be interested in your other planting guides for Calumet City.