One of the best tools that you have as gardeners to help us estimate 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.

By reviewing the USDA zone info for Miles City it's a good idea to figure out when to plant bidens.

Planting Calendar for Bidens

Frost tolerance for bidens:	Not tolerant of frost.
When to plant:	After the last frost.

Since bidens are not cold tolerant it's important to wait until after the last frost has passed before you can plant them.

The earliest that you can plant bidens in Miles City is May. However, you really should wait until June if you don't want to take any chances.

The last month that you can plant bidens and expect a good harvest is probably August. You probably don't want to wait any later than that or else your bidens may not have a chance to fully mature. You can get started a couple of weeks earlier by starting your bidens indoors.

Last Frost Date

The average date of last frost is May 15 in Miles City. You can expect an average low temperature of -30°F in the coldest months of winter.

Since the USDA zone info for Miles City is not always accurate the actual date of last frost will vary from year to year. Since half of the time in Miles City last frost occurs after May 15 be ready to protect your bidens in the event of one of those late frosts.

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.