When to Plant Hardy Hibiscus in Grinnell, IA

One of the first steps you take when you are making a decision about 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.

You can estimate when you can plant hardy hibiscus in Grinnell by using the USDA zone info.


Planting Calendar for Hardy Hibiscus

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

Hardy Hibiscus tend to make it in cold weather which means that you can plant them much earlier in the year than other plants that might not handle 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 Grinnell is February. However, you really should wait until March 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 September. If you wait any later than that and your hardy hibiscus may not have a chance to really do well. If you are starting your hardy hibiscus indoors then you might be able to get away with starting them a few weeks earlier.

Last Frost Date

On average the last frost has passed is on April 15 in Grinnell. You can expect an average low temperature of -20°F in the coldest months of winter.

Remember that the actual date of last frost is an average because it is based on the USDA zone info for Grinnell and it is different every year. Since half of the time in Grinnell you get a frost after April 15 be ready to protect your hardy hibiscus if you have a late frost.

USDA Zone Info for Grinnell

Here is the info for USDA Zone 5a.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-20°F
Highest Expected Low-15°F

This means that on a really cold year, the coldest it will get is -20°F. On most years you should be prepared to experience lows near -15°F.

Plants to Grow in Grinnell

You may be interested in your other planting guides for Grinnell.