One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The most important data that the zone info tells us is average last frost and the lowest expected temperature for your area.

The first opportunity to plant coreopsis in Iron Mountain should be estimated by looking at the USDA zone info.

Planting Calendar for Coreopsis

Frost tolerance for coreopsis:	Tolerant of some frost.
When to plant:	Up to 5 weeks before last frost.

You can plant coreopsis a little earlier in the year because they are moderately cold tolerant.

The earliest that you can plant coreopsis in Iron Mountain 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 coreopsis and expect a good harvest is probably August. You probably don't want to wait any later than that or else your coreopsis may not have a chance to fully mature. Starting your coreopsis indoors is a great way to get them started a little bit earlier.

Last Frost Date

On average the last frost when the weather gets warmer is on May 15 in Iron Mountain. It might get as low as -30°F during the coldest months of winter.

Keep in mind that USDA zone info for Iron Mountain is an average and the actual date of last frost will vary from year to year. Half of the time in Iron Mountain there is a last frost after May 15 so always be ready to cover your coreopsis in the event of a surprise late frost.

USDA Zone Info for Iron Mountain

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 Iron Mountain

You may be interested in your other planting guides for Iron Mountain.