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

A way of estimating when it's the best time to plant pennyroyal is to examine the USDA zone info for Aurora.

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 quite a bit of cold which tells us that you can plant them quite a bit earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in Aurora 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 few weeks earlier by starting your pennyroyal indoors.

Last Frost Date

In Aurora the average date of last frost happens on April 15. It might get as low as -15°F during the coldest months of winter.

Since the USDA zone info for Aurora is just an average the actual date of last frost is different every year. Since half of the time in Aurora there is a last frost after April 15 be ready to cover your pennyroyal in the event of a late frost.

USDA Zone Info for Aurora

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-15°F
Highest Expected Low	-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Aurora

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