Before planting it is a good idea to find your USDA Zone info to figure out 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.

The first opportunity to plant pennyroyal in Manhattan should be figured out by reviewing 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.

Pennyroyal are one of those plants that can tolerate quite a bit of cold weather which means that you can plant them a quite a bit earlier than other plants that might not handle the cold.

The earliest that you can plant pennyroyal in Manhattan 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 grow to maturity. You can get started a few weeks earlier by starting your pennyroyal indoors.

Last Frost Date

In Manhattan the average date of last frost happens on April 15. In the coldest months of winter you should expect an average low temperature of -10°F.

Since the USDA zone info for Manhattan may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Manhattan last frost occurs after April 15 be ready to protect your pennyroyal in the event of one of those late frosts.

USDA Zone Info for Manhattan

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 Manhattan

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