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.

One way of determining when to plant pennyroyal is to examine the USDA zone info for Lapeer.

Planting Calendar for Pennyroyal

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

Since pennyroyal are one of those plants that can tolerate quite a bit of cold weather you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in Lapeer 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 grow to maturity. You can get started a little bit earlier by starting your pennyroyal indoors.

Last Frost Date

The average date of last frost is April 15 in Lapeer. You can expect an average low temperature of -15°F in the coldest months of winter.

Since the USDA zone info for Lapeer is not always accurate the actual date of last frost can change quite a bit from year to year. Half of the time in Lapeer there is a last frost after April 15 so make sure that you are prepared to protect your pennyroyal in the event of a surprise late frost.

USDA Zone Info for Lapeer

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 Lapeer

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