One of the first steps you take when you are making a decision about your gardening schedule is find your 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.

The USDA zone info for Manitowoc should be read to figure out when it's the best time to plant pennyroyal.

Planting Calendar for Pennyroyal

Frost tolerance for pennyroyal:	Very tolerant of frost.
When to plant:	Up to 7 weeks before last frost.

Pennyroyal are very cold tolerant which means that you can start planting them much earlier than other plants that might not handle the cold.

The earliest that you can plant pennyroyal 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 pennyroyal and expect a good harvest is probably September. Any later than that and your pennyroyal may not have a chance to really do well. If you are starting your pennyroyal 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.

Since the USDA zone info for Manitowoc is just an average the actual date of last frost can change quite a bit from year to year. Half of the time in Manitowoc you get surprised by a frost after April 15 so make sure that you are prepared to protect your pennyroyal in the event of 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.