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 determine when it's possible to plant impatiens in Iron Mountain by referring to the USDA zone info.

Planting Calendar for Impatiens

Frost tolerance for impatiens:	Not tolerant of frost.
When to plant:	After the last frost when the weather gets warmer.

Since impatiens require warm weather you have to wait until after the last frost has passed before you can plant them.

The earliest that you can plant impatiens in Iron Mountain 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 impatiens and expect a good harvest is probably August. You probably don't want to wait any later than that or else your impatiens may not have a chance to fully mature. You can get started a few weeks earlier by starting your impatiens indoors.

Last Frost Date

In Iron Mountain the average date of last frost happens on May 15. You can expect an average low temperature of -30°F in the coldest months of winter.

Remember that USDA zone info for Iron Mountain is an average and the actual date of last frost can change quite a bit from year to year. Half of the time in Iron Mountain you get surprised by a frost after May 15 so make sure that you are ready to protect your impatiens if you have one of those late frosts.

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.