Before planting it is a good idea to find your USDA Zone info to estimate your garden schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Springfield you can determine when it's a good idea to plant pennyroyal by checking out 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 a lot earlier in the year because they do well in cold.

The earliest that you can plant pennyroyal in Springfield is January. However, you really should wait until February if you don't want to take any chances.

The last month that you can plant pennyroyal and expect a good harvest is probably October. Any later than that and your pennyroyal may not have a chance to grow to maturity. Starting your pennyroyal indoors is a great way to get them started a few weeks earlier.

Last Frost Date

In Springfield the average date of last frost happens on February 15. You should expect an average low temperature of 20°F in the coldest months of winter.

Since the USDA zone info for Springfield is an average the actual date of last frost changes from year to year. Since half of the time in Springfield you get surprised by a frost after February 15 be ready to protect your pennyroyal if you have one of those late frosts.

USDA Zone Info for Springfield

Here is the info for USDA Zone 9a.

Average Date of Last Frost (spring)	February 15
Average Date of First Frost (fall)	December 15
Lowest Expected Low	20°F
Highest Expected Low	25°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 25°F.

Plants to Grow in Springfield

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