The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

You can estimate when it's possible to plant pennyroyal in Miles City by reviewing 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 Miles City is March. However, you really should wait until April if you don't want to take any chances.

The last month that you can plant pennyroyal and expect a good harvest is probably August. If you wait any later than that and your pennyroyal may not have a chance to grow to maturity. You can get started a little bit earlier by starting your pennyroyal indoors.

Last Frost Date

In Miles City the average date of last frost happens on May 15. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Miles City may not be accurate from year to year the actual date of last frost is different every year. Since half of the time in Miles City last frost occurs after May 15 be ready to protect your pennyroyal if you have a surprise late frost.

USDA Zone Info for Miles City

Here is the info for USDA Zone 4a.

Average Date of Last Frost (spring)	May 15
Average Date of First Frost (fall)	September 15
Lowest Expected Low	-30°F
Highest Expected Low	-25°F

This means that on a really cold year, the coldest it will get is -30°F. On most years you should be prepared to experience lows near -25°F.

Plants to Grow in Miles City

You may be interested in your other planting guides for Miles City.