When to Plant Hardy Hibiscus in Lisle, IL

One of the best tools that you have as gardeners to help us estimate your gardening schedule is the 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.

The USDA zone info for Lisle can be reffered to in order to determine when it's the best time 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.

Hardy Hibiscus do ok in pretty solid cold which means that you can plant them a lot 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 Lisle 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. You probably don't want to wait any later than that or else your hardy hibiscus may not have a chance to fully mature. 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

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

Since the USDA zone info for Lisle may not be accurate from year to year the actual date of last frost is different every year. Half of the time in Lisle it frosts late in the year after April 15 so make sure that you are ready to protect your hardy hibiscus if you have a late frost.

USDA Zone Info for Lisle

Here is the info for USDA Zone 5b.

Average Date of Last Frost (spring)April 15
Average Date of First Frost (fall)October 15
Lowest Expected Low-15°F
Highest Expected Low-10°F

This means that on a really cold year, the coldest it will get is -15°F. On most years you should be prepared to experience lows near -10°F.

Plants to Grow in Lisle

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