The USDA Zone info is a great tool for gardeners to help us estimate your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Marshall you can figure out when you can plant pennyroyal by checking out 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 tells us that you can plant them a quite a bit earlier than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in Marshall 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 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 Marshall. It might get as low as -10°F during the coldest months of winter.

Since the USDA zone info for Marshall is just an average the actual date of last frost will vary from year to year. Half of the time in Marshall you get surprised by a 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 Marshall

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 Marshall

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