One of the first steps you take when you are estimating 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.

It's possible to figure out when to plant pennyroyal by looking at the USDA zone info for Cedar Rapids.

Planting Calendar for Pennyroyal

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

Since pennyroyal are very cold tolerant you can plant them quite a bit earlier in the year than other plants that might not handle the cold.

The earliest that you can plant pennyroyal in Cedar Rapids 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. Starting your pennyroyal indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is April 15 in Cedar Rapids. In the coldest months of winter you can expect an average low temperature of -20°F.

Since the USDA zone info for Cedar Rapids is just an average the actual date of last frost changes from year to year. Since half of the time in Cedar Rapids you get surprised by a frost after April 15 be ready to cover your pennyroyal in the event of a surprise late frost.

USDA Zone Info for Cedar Rapids

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 Cedar Rapids

You may be interested in your other planting guides for Cedar Rapids.