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

By referring to the USDA zone info for Waukee you should be able to estimate when to plant pennyroyal.

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 pretty solid cold which tells us that you can plant them earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pennyroyal in Waukee 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 couple of weeks earlier by starting your pennyroyal indoors.

Last Frost Date

On average the last frost has passed is on April 15 in Waukee. You can expect an average low temperature of -20°F in the coldest months of winter.

Since the USDA zone info for Waukee is just an average the actual date of last frost changes from year to year. Since half of the time in Waukee there is a last frost after April 15 be ready to protect your pennyroyal in the event of a surprise late frost.

USDA Zone Info for Waukee

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-20°F
Highest Expected Low	-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Waukee

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