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.

By looking at the USDA zone info for Tiffin it's possible to figure out when 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 can survive in quite a bit of cold which means that you can plant them earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in Tiffin 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 fully mature. You can get started a little bit earlier by starting your pennyroyal indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Tiffin. You can expect an average low temperature of -10°F in the coldest months of winter.

Since the USDA zone info for Tiffin may not be accurate from year to year the actual date of last frost changes from year to year. Half of the time in Tiffin there is a last frost after April 15 so make sure that you are ready to cover your pennyroyal if you have a late frost.

USDA Zone Info for Tiffin

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Tiffin

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