One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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 determining when to plant penstemon is to refer to the USDA zone info for Chester.

Planting Calendar for Penstemon

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

Penstemon are moderately cold tolerant which tells us that you can get them planted earlier than plants that are more sensitive to the cold.

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

Since the USDA zone info for Chester is an average the actual date of last frost is different every year. Since half of the time in Chester last frost occurs after April 15 be ready to cover your penstemon if you have one of those late frosts.

USDA Zone Info for Chester

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 Chester

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