The USDA Zone info is a great tool for gardeners to help us figure out your gardening schedule. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

A way of getting a good idea when it's the best time to plant verbena is to consult the USDA zone info for Iron Mountain.

Planting Calendar for Verbena

Frost tolerance for verbena:	Tolerant of a very small amount of frost.
When to plant:	Up to 3 weeks before last frost.

Verbena do well in very little cold which means that you can plant them a bit earlier in the year than more sensitive plants.

The earliest that you can plant verbena in Iron Mountain is April. However, you really should wait until May if you don't want to take any chances.

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

Last Frost Date

On average the last frost is on May 15 in Iron Mountain. In the coldest months of winter you should expect an average low temperature of -30°F.

It's important to remember that USDA zone info for Iron Mountain is just 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 last frost occurs after May 15 so just be sure to be ready to protect your verbena if you have a 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.