When to Plant Hardy Hibiscus in Slinger, WI

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the USDA zone info. The zone info helps tell us things like average date of last frost and lowest expected temperature for your area.

In Slinger you can estimate when you can plant hardy hibiscus by looking at 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.

You can plant hardy hibiscus much earlier in the year because they are one of those plants that can tolerate quite a bit of cold weather.

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 Slinger 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. Any later than that and your hardy hibiscus may not have a chance to fully mature. You can get started a few weeks earlier by starting your hardy hibiscus indoors.

Last Frost Date

The average date of last frost is April 15 in Slinger. In the coldest months of winter you can expect an average low temperature of -20°F.

Remember that the actual date of last frost is not always accurate because it is based on the USDA zone info for Slinger and it can change quite a bit from year to year. Half of the time in Slinger there is a last frost after April 15 so make sure that you are prepared to protect your hardy hibiscus in the event of a surprise late frost.

USDA Zone Info for Slinger

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 Slinger

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