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.

The best time to plant pennyroyal in Lake Bluff should be figured out by looking at 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.

You can plant pennyroyal much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

The earliest that you can plant pennyroyal in Lake Bluff 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 fully mature. 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 Lake Bluff. In the coldest months of winter you can expect an average low temperature of -15°F.

Since the USDA zone info for Lake Bluff may not be accurate from year to year the actual date of last frost can change quite a bit from year to year. Half of the time in Lake Bluff last frost occurs after April 15 so make sure that you are ready to protect your pennyroyal in the event of a surprise late frost.

USDA Zone Info for Lake Bluff

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 Lake Bluff

You may be interested in your other planting guides for Lake Bluff.