One of the first steps you take when you are figuring out your gardening schedule is find your USDA Zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Iron Mountain you can figure out when to plant hollyhocks by using the USDA zone info.

Planting Calendar for Hollyhocks

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

Since hollyhocks are moderately cold tolerant you can plant them a little bit earlier in the year than other frost tender plants.

The earliest that you can plant hollyhocks 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 hollyhocks and expect a good harvest is probably August. Any later than that and your hollyhocks may not have a chance to grow to maturity. Starting your hollyhocks indoors is a great way to get them started a little bit earlier.

Last Frost Date

The average date of last frost is May 15 in Iron Mountain. It might get as low as -30°F during the coldest months of winter.

Since the USDA zone info for Iron Mountain is an average 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 protect your hollyhocks in the event of 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.