Before planting it is a good idea to find your USDA Zone info to estimate 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.

By checking out the USDA zone info for Westerville you will be able to estimate when it's a good idea to 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 moderate cold which means that you can start planting them earlier than more sensitive plants.

The earliest that you can plant penstemon in Westerville 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. Any later than that and your penstemon may not have a chance to grow to maturity. 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 Westerville. You should expect an average low temperature of -10°F in the coldest months of winter.

Keep in mind that USDA zone info for Westerville may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Since half of the time in Westerville last frost occurs after April 15 be ready to protect your penstemon if you have a late frost.

USDA Zone Info for Westerville

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 Westerville

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