One of the best tools that you have as gardeners to help us figure out your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when you can plant penstemon in Manitowoc by looking at the USDA zone info.

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 means that you can plant them a little bit earlier than more sensitive plants.

The earliest that you can plant penstemon in Manitowoc 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 really do well. 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

The average date of last frost is April 15 in Manitowoc. It might get as low as -15°F during the coldest months of winter.

Just be sure to remember that USDA zone info for Manitowoc is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Manitowoc you get surprised by a frost after April 15 be ready to protect your penstemon if you have a late frost.

USDA Zone Info for Manitowoc

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 Manitowoc

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