When to Plant Penstemon in Naperville, IL

Before planting it is a good idea to find your USDA Zone info to figure out your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

One way of making a decision about when to plant penstemon is to refer to the USDA zone info for Naperville.


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 tells us that you can plant them a little bit earlier in the year than other plants that might not handle the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant penstemon
Possibly ok, but a risky time to plant penstemon
Probably not a good time to plant penstemon

The earliest that you can plant penstemon in Naperville 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 fully mature. Starting your penstemon indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on April 15 in Naperville. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Naperville is just an average the actual date of last frost changes from year to year. Since half of the time in Naperville you get surprised by a frost after April 15 be ready to protect your penstemon in the event of a late frost.

USDA Zone Info for Naperville

Here is the info for USDA Zone 5b.

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

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Naperville

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