One of the best tools that you have as gardeners to help us determine your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

The USDA zone info for Butler should be looked at to figure out when it's possible 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 tend to make it in cold weather which means that you can plant them a lot earlier in the year than other frost tender plants.

The earliest that you can plant pennyroyal in Butler 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. Any later than that and your pennyroyal may not have a chance to fully mature. If you are starting your pennyroyal indoors then you might be able to get away with starting them a couple of weeks earlier.

Last Frost Date

On average all chance of frost has passed is on April 15 in Butler. It might get as low as -10°F during the coldest months of winter.

Remember that USDA zone info for Butler is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Butler it frosts late in the year after April 15 so make sure that you are prepared to protect your pennyroyal in the event of a late frost.

USDA Zone Info for Butler

Here is the info for USDA Zone 6a.

Average Date of Last Frost (spring)	April 15
Average Date of First Frost (fall)	October 15
Lowest Expected Low	-10°F
Highest Expected Low	-5°F

This means that on a really cold year, the coldest it will get is -10°F. On most years you should be prepared to experience lows near -5°F.

Plants to Grow in Butler

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