One of the first steps you take when you are getting a good idea your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

You should be able to estimate when it's possible to plant pennyroyal by using the USDA zone info for Shawano.

Planting Calendar for Pennyroyal

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

You can plant pennyroyal earlier in the year because they are very cold tolerant.

The earliest that you can plant pennyroyal in Shawano is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant pennyroyal and expect a good harvest is probably August. If you wait any later than that and your pennyroyal may not have a chance to fully mature. You can get started a few weeks earlier by starting your pennyroyal indoors.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Shawano. In the coldest months of winter you should expect an average low temperature of -25°F.

Since the USDA zone info for Shawano may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Shawano you get a frost after May 15 so make sure that you are ready to cover your pennyroyal in the event of one of those late frosts.

USDA Zone Info for Shawano

Here is the info for USDA Zone 4b.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-25°F
Highest Expected Low	-20°F

This means that on a really cold year, the coldest it will get is -25°F. On most years you should be prepared to experience lows near -20°F.

Plants to Grow in Shawano

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