One of the first steps you take when you are making a decision about your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of making a decision about when to plant pennyroyal is to refer to the USDA zone info for Salem.

Planting Calendar for Pennyroyal

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

Pennyroyal do well in cold which tells us that you can plant them much earlier than other frost tender plants.

The earliest that you can plant pennyroyal in Salem 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 really do well. 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 Salem. In the coldest months of winter you should expect an average low temperature of -10°F.

Always keep in mind that USDA zone info for Salem may not be accurate from year to year and the actual date of last frost can change quite a bit from year to year. Half of the time in Salem last frost occurs after April 15 so be sure to be ready to protect your pennyroyal if you have a surprise late frost.

USDA Zone Info for Salem

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 Salem

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