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.

A way of getting a good idea when you can plant pennyroyal is to check out the USDA zone info for Sun Prairie.

Planting Calendar for Pennyroyal

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

Pennyroyal do well in a bit of cold which means that you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pennyroyal in Sun Prairie 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. You probably don't want to wait any later than that or else 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

The average date of last frost is April 15 in Sun Prairie. It might get as low as -20°F during the coldest months of winter.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Sun Prairie and it changes from year to year. Half of the time in Sun Prairie there is a last frost after April 15 so just be sure to be ready to cover your pennyroyal if you have one of those late frosts.

USDA Zone Info for Sun Prairie

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Sun Prairie

You may be interested in your other planting guides for Sun Prairie.