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 way of estimating when you can plant pennyroyal is to look at the USDA zone info for Signal Mountain.

Planting Calendar for Pennyroyal

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

You can plant pennyroyal quite a bit earlier in the year because they do well in cold.

The earliest that you can plant pennyroyal in Signal Mountain 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 fully mature. You can get started a couple of weeks earlier by starting your pennyroyal indoors.

Last Frost Date

The average date of last frost is April 15 in Signal Mountain. In the coldest months of winter you should expect an average low temperature of 0°F.

Since the USDA zone info for Signal Mountain is not always accurate the actual date of last frost changes from year to year. Half of the time in Signal Mountain there is a last frost after April 15 so just be sure to be ready to protect your pennyroyal if you have one of those late frosts.

USDA Zone Info for Signal Mountain

Here is the info for USDA Zone 7a.

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

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

Plants to Grow in Signal Mountain

You may be interested in your other planting guides for Signal Mountain.