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MAY 31, 2026
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What Growing Zone Is Flanagan?

Our records indicate the United States Department of Agriculture has given Flanagan a growing zone designation of 5b. Sometimes also called the planting or hardiness zone, this zone number gives you an idea of what plants can and cannot grow in Flanagan's climate based on the average extreme annual temperature.Our data is based on the latest 2023 USDA maps, which used Flanagan's weather data from 1991 - 2020 in their analysis.

β€” Plate β€”IL Β· USDA hardiness
map of growing zone 5b
Latest IL growing zone map

If you are looking for plants suitable for growing in the Flanagan area, head on over to our page on plants that grow well in Flanagan, IL.

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Show Flanagan's growing zone on my site

β€” Plate β€”IL Β· USDA hardiness
map of growing zone 5b
Latest IL growing zone map

The growing zone is a measure of the lowest temperature that a plant can survive based on average lowest year temperatures, helping you to decide what plants would grow best in your particular climate. Since Flanagan is in growing zone 5b this means that plants there can survive temperatures as low as -15 to -10 degrees Fahrenheit. Plants for Flanagan's climate should be chosen with this in mind, or plants should be moved inside to keep their core temperature in the right range if necessary.

Some zones may have been changed by the USDA as of 2023. To see if the Flanagan area has been affected, refer to this map of half zone changes from the 2012 version of the USDA zones to the 2023 version.

The updated map shows that over half of the Southeast has warmed by about half a zone. For gardeners, that means you can now grow plants that tolerate a bit more heat and less frost than before. The tan areas reflect this shift. Meanwhile, the white areas had slight temperature changes, but not enough to move them into a new zone. In the Western U.S., a few spots shifted cooler. That’s not due to a colder climate, but because the new map uses a larger dataset, giving a more accurate picture of local conditions. It's important to keep track of these changes when planning your garden!

Ready to start planning your garden? Browse our curated list of plants recommended for Flanagan, IL that are matched to this hardiness zone.

Hardiness Zone FAQ

Have questions about hardiness zones and what they mean for your garden? Check out our FAQ below for quick answers to common questions about USDA hardiness zones and how they affect plant selection in Flanagan, IL.

β„– 01What hardiness zone is Flanagan, IL?+

The USDA hardiness zone is 5b for Flanagan. This is sometimes also referred to as the growing or planting zone. These terms are used interchangeably.

β„– 02What does growing zone 5b mean for Flanagan, IL?+

Growing zone 5b means that plants in Flanagan, IL can survive temperatures as low as -15 to -10 degrees Fahrenheit. This zone designation helps you choose plants that will thrive in your local climate conditions.

β„– 03How do I use the growing zone information for Flanagan?+

Keep your growing zone of 5b in mind when choosing plants for Flanagan. The growing zone tells you the average low temperatures that occur each year in Flanagan. If you select plants from zones other than 5b, then you may need to provide additional care during the coldest months of the year.

β„– 04Has Flanagan's growing zone changed?+

The USDA updated their hardiness zone maps in 2023. As a result, Flanagan may have experienced zone changes. Some areas of the Southeast warmed by half a zone, while areas of the Western United States had their zones lowered as a result of additional data becoming available.

β„– 05What plants grow best in zone 5b?+

Visit our page on the best plants for Flanagan to see a full list recommendations for the area.

β„– 06Can I grow plants from other zones in Flanagan?+

While you can try plants from other zones, they may need winter protection or indoor shelter during cold spells. Focus on plants recommended for Flanagan's climate for the best results.

Flanagan's Growing Zone Details

USDA Growing Zone: 5b

Zip Codes:

Longitude: -88.8596

Latitude: 40.8771

Lowest Avg Temperatures (F): -15 to -10

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Map of the Flanagan Area

β€” Map β€”Lat 40.8771, Lon -88.8596
Tile data Β© Google Maps

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Plants For Other States

Looking for the best plants in a different area of the United States? Click on a button below to find plants that are ideal for that state's temperatures.

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