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 Clarendon Hills you can determine when to plant pennyroyal by using 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.

Since pennyroyal do well in cold you can plant them a lot earlier in the year than plants that are more sensitive to the cold.

The earliest that you can plant pennyroyal in Clarendon Hills 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 grow to maturity. 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 Clarendon Hills. It might get as low as -15°F during the coldest months of winter.

Always keep in mind that USDA zone info for Clarendon Hills is not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Clarendon Hills there is a last frost after April 15 be ready to protect your pennyroyal if you have a surprise late frost.

USDA Zone Info for Clarendon Hills

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 Clarendon Hills

You may be interested in your other planting guides for Clarendon Hills.