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.

In Winona you can figure out when to plant pennyroyal by using the USDA zone info.

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 quite a bit earlier in the year because they are very cold tolerant.

The earliest that you can plant pennyroyal in Winona 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

The average date of last frost is May 15 in Winona. You should expect an average low temperature of -25°F in the coldest months of winter.

Remember that the actual date of last frost is just an average because it is based on the USDA zone info for Winona and it will vary from year to year. Since half of the time in Winona you get surprised by a frost after May 15 be ready to protect your pennyroyal if you have a late frost.

USDA Zone Info for Winona

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 Winona

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