The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. 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 to plant penstemon is to consult the USDA zone info for West Mifflin.

Planting Calendar for Penstemon

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

Since penstemon are moderately cold tolerant you can plant them a little earlier in the year than other plants that might not handle the cold.

The earliest that you can plant penstemon in West Mifflin 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 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

The average date of last frost is April 15 in West Mifflin. You should expect an average low temperature of -5°F in the coldest months of winter.

Since the USDA zone info for West Mifflin is just an average the actual date of last frost is different every year. Half of the time in West Mifflin last frost occurs after April 15 so make sure that you are prepared to protect your penstemon in the event of a late frost.

USDA Zone Info for West Mifflin

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 West Mifflin

You may be interested in your other planting guides for West Mifflin.