frostdate name logo in white
frostdate name logo in white

When to Plant Hardy Hibiscus in Iron Mountain, MI

One of the first steps you take when you are determining your gardening schedule is find your 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.

By referring to the USDA zone info for Iron Mountain you will be able to estimate when it's a good idea to plant hardy hibiscus.


Planting Calendar for Hardy Hibiscus

Frost tolerance for hardy hibiscus: Very tolerant of frost.
When to plant: Up to 7 weeks before last frost.

Since hardy hibiscus are one of those plants that can tolerate quite a bit of cold weather you can plant them much earlier in the year than plants that are more sensitive to the cold.

JanFebMarAprMayJunJulAugSepOctNovDec
Legend 
A good time to plant hardy hibiscus
Possibly ok, but a risky time to plant hardy hibiscus
Probably not a good time to plant hardy hibiscus

The earliest that you can plant hardy hibiscus 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 hardy hibiscus and expect a good harvest is probably August. If you wait any later than that and your hardy hibiscus may not have a chance to grow to maturity. Starting your hardy hibiscus indoors is a great way to get them started a couple of weeks earlier.

Last Frost Date

In Iron Mountain the average date of last frost happens on May 15. 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 not always accurate and the actual date of last frost can change quite a bit from year to year. Since half of the time in Iron Mountain last frost occurs after May 15 be ready to cover your hardy hibiscus in the event of 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.