Before planting it is a good idea to find your USDA Zone info to determine your garden schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

A common way of getting a good idea when it's possible to plant pennyroyal is to refer to the USDA zone info for Middlesex.

Planting Calendar for Pennyroyal

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

Pennyroyal do ok in a bit of cold which means that you can plant them much earlier in the year than more sensitive plants.

The earliest that you can plant pennyroyal in Middlesex 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. If you wait any later than that and your pennyroyal may not have a chance to really do well. You can get started a few weeks earlier by starting your pennyroyal indoors.

Last Frost Date

On average all chance of frost has passed is on April 15 in Middlesex. In the coldest months of winter you should expect an average low temperature of -5°F.

Always keep in mind that the actual date of last frost may not be accurate from year to year because it is based on the USDA zone info for Middlesex and it will vary from year to year. Half of the time in Middlesex there is a last frost after April 15 so just be sure to be ready to cover your pennyroyal if you have a surprise late frost.

USDA Zone Info for Middlesex

Here is the info for USDA Zone 6b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-5°F
Highest Expected Low	0°F

This means that on a really cold year, the coldest it will get is -5°F. On most years you should be prepared to experience lows near 0°F.

Plants to Grow in Middlesex

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