USDA Hardiness Zones: What Does Your Zone Mean?

usda hardiness zones
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What are your USDA Hardiness Zones? If you’re not sure, usda.gov has a map that can tell you! It’s important to know what zone you live in because it will determine which plants are best for your area. In this blog post, we’ll explore the different zones and the types of plants that grow well in each one so you can find the perfect plant for your garden!

What USDA hardiness zones won’t tell you?

USDA hardiness zones won’t tell you about regional growing conditions. These are things like soil type, rainfall, and humidity levels. This means that even if your plant is rated for a zone lower than yours, it might not do very well in your garden due to the different weather conditions where you live. It’s important to take this into consideration when planning your garden and deciding what plants to grow.

What USDA hardiness zones will tell you

USDA hardiness zones give an estimate of the coldest winter temperatures a plant can survive in, based on its location in North America. This is important because it’s the difference between life and death for plants. The USDA hardiness zones are divided into ten-degree increments, with each zone being a minimum of ten degrees warmer than the one before it.

What are planting zones?

usda hardiness zones

Planting zones are USDA hardiness zone designations for flower and vegetable seeds and transplants. The USDA has not created a single planting zone map; they’ve divided us into ten separate regions, each with different minimum winter temperatures. Each region is broken down further – by state – within the larger USDA growing zones used to determine USDA plant hardiness.

The USDA planting zone map is based on the average winter low temperatures in that area, not the coldest it ever gets. This means that even if you live within one of USDA growing zones but your region experiences colder-than-average winters, you may need to grow plants rated for a warmer USDA zone.

The USDA hardiness zones are a good way to know the minimum temperature a plant can survive, but there’s so much more to consider when determining what plants will thrive in your garden!

How to use your planting zone

You can find your USDA planting zone by looking at the map with your zip code.

USDA hardiness zones have two map types: one for lower and another for higher elevations (denoted in red). The upper boundary of a plant’s USDA hardiness zones is calculated on average minimum temperature while the lower limit is based on USDA average maximum temperature.

Typical USDA hardiness zones by region

usda hardiness zones

The U.S Department of Agriculture (USDA) has divided the United States into hardiness zones for over 100 years, and each zone is based on what can be grown there in average winter temperatures.

The USDA no longer uses this system to define planting zones but it’s still a popular way to determine where to plant vegetation. Depending upon how you interpret the data, there may be several different USDA hardiness zones for each state.

North Central USDA Hardiness Zones

The North Central U.S. is divided into 11 zones, from zone one to zone eleven, with each number representing a decrease in cold winter temperatures as you move further north. The southernmost part of the United States includes states like Texas that have warm climates and mild winters but can also include areas such as much of Arkansas that are cold with harsh winters.

For most of the United States, there are only two hardiness zones but some areas have three or more because they experience a wider range of temperatures and can be affected by other weather patterns such as winds that bring in warm air from the south or ocean currents that move colder water into their coastal regions. This is why coastal areas may have warmer weather than you would expect for their zone.

The following are the eleven North Central U.S. hardiness zones according to the USDA:

Zone one

Minnesota, Wisconsin, Michigan, and most of New York state with a few exceptions near Lake Ontario in NY; Ohio River Valley including parts of KY, IN, IL and MO; small areas of IA as well

Zone two

Northern New York state spread through much of VT, NH, ME, and upstate NY; most of MI except the southern lower peninsula, where it is zone three instead

Zone three

Southcentral Michigan: Ann Arbor and Detroit area northward to include almost all of upper peninsula; northern Indiana and Ohio River Valley west to include Columbus, OH

Zone four

Northern Michigan including the entire upper peninsula; most of central & eastern Wisconsin (Madison is in zone five)

Zone five

Northern Wisconsin: Green Bay/Fox Cities area northward to border on Lake Superior. Most of IA south of Mason City up to Minnesota border including Des Moines, IA

Zone six

The eastern half of North Dakota and South Dakota; northern Nebraska up to the NE/SD state line; most of Kansas except south-central region which is in zone eight instead. All but the easternmost tip of Oklahoma is also included here.

Zone seven

Southern third or so of North Dakota, South Dakota, and Nebraska; the eastern half of Kansas south to Wichita area

Zone eight

Eastern third or so of North Dakota, South Dakota & NE/SD border westward through the middle part of Iowa. Most but not all of Missouri is also included here as well as the southernmost tip of Minnesota including the Minneapolis/St Paul metro area.

Zone nine

The northern third of Iowa and the southernmost tip of Minnesota as well as much of WI northward to Lake Superior.

Zone ten

Central third or so of South Dakota, most but not all of North Dakota, and central/northern Nebraska west to Omaha area; northern half & eastern edge (northwest corner) only of Kansas

Zone eleven

Most of North Dakota, most but not all of South Dakota; the eastern half of Nebraska west to Omaha area. No states are included in this zone although there is an isolated small part of SD on the far western edge that comes close to it (it’s at 47° latitude).

North East USDA Hardiness Zones

The North East U.S. is divided into five zones, from zone one to zone five, with each number representing a decrease in cold winter temperatures as you move further north and east away from the Great Lakes. The northern states of New York and Pennsylvania have two hardiness zones but the southern parts such as Maryland are included in zone five.

Zone one

Northern New York state and most of the upper peninsula in Michigan

Zone two

Western half or so of MI including the Lansing/Jackson area; southern third or so of Wisconsin down to border with Illinois & northwest corner of IN near Chicago

Zone three

Central third or so of WI southward around the Great Lakes to the WI/IL border; northern half or so of IN away from Lake Michigan

Zone four

Southern third or so of WI down to Milwaukee area and most but not all of IL southward around Chicago area

Zone five

Most if not all of Illinois as well as eastern half & southern tip only of Indiana, lower peninsula MI, and most of OH southward around Cincinnati area except southwest corner near Dayton

North West USDA Hardiness Zones

The North West U.S. is divided into three zones, from zone one to zone three, with each number representing a decrease in cold winter temperatures as you move further north and west away from the Great Lakes.

Zone one

Most of Wisconsin down to the border with Illinois & northwest corner of IN near Chicago

Zone two

Central third or so of WI southward around the Great Lakes to the WI/IL border; northern half or so of IN away from Lake Michigan

Zone three

Southern third or so of WI down to Milwaukee area and most but not all of IL southward around Chicago area. Most if not all MI except far western edge & northwest corner near the upper peninsula.

All but the easternmost tip of Oklahoma is also included here as well as a small part on the far western edge of MO.

South Central USDA Hardiness Zones

The South Central U.S. is divided into five zones, from zone one to zone five, with each number representing a decrease in cold winter temperatures as you move further south and away from the Great Lakes/Rockies which runs along most of the western edge.

Zone one

Central third or so of North Dakota, South Dakota & NE/SD border westward through the middle part of Iowa. Most but not all of Missouri is also included here as well as the southernmost tip of Minnesota including the Minneapolis/St Paul metro area

Zone two

Most if not all North Dakota, western half or so only of South Dakota; eastern half Nebraska away from Omaha to the far eastern tip of the state

Zone three

Most but not all of Iowa southward to central Missouri

Zone four

Southern third or so only of Iowa from near Des Moines westward, southern half & western edge (northwest corner) only in KS away from the metro area. Also includes a small part on the far western edge of MO.

Zone five

Eastern half only of Kansas, eastern third or so only of NE away from Omaha to the far eastern tip of the state. A small part on the western edge near Denver has also included here as well as a tiny section at 47° latitude in far southwest Missouri which comes close but not quite to zone four thanks to its more southern latitude.

South East USDA Hardiness Zones

The South East U.S. is divided into six zones, from zone one to zone six, with each number representing a decrease in cold winter temperatures as you move further south and away from the Great Lakes/Rockies which runs along most of the western edge; also known as “fall line” or “approximate Fall Line”

Zone one

Most of West Virginia down to the border with North Carolina, eastern third or so only in NC away from the metro area. Also includes a small part on the western edge near Knoxville along TN/VA border; northeastern corner of SC; the far northeast tip of GA including Atlanta Metro Area

Zone two

A small area on the far western edge of NC near Asheville & a tiny part of SC southward from Greenville-Spartanburg Metro Area.

Zone three

Most if not all of North Carolina away from metro areas including Charlotte and Raleigh/Durham, TN westward to Cookeville; most but not all northwest corner only in SC

Zone four

Eastern half or so of TN, eastern third only in NC away from Charlotte and Winston-Salem Metro Area; western two-thirds or so & all but the north-central tip of GA outside metro areas. Also includes a small part on the far western edge near Birmingham along AL/TN border as well as some parts at 47° latitude in far southwest MO.

Zone five

Most of TN outside metro areas, all but the north-central tip of GA within Metro Areas; most if not all KY away from Louisville/Lexington area to the west and southward along the state border with Tennessee & Alabama line

Zone six

Eastern half only in KY around Louisville/Lexington, southern half or so & western edge only in TN away from Knoxville Metro Area; most of AL including Birmingham/Anniston Metro Areas.

May include some parts at 47° latitude in far southwest MO as well as a small part on the eastern edge near Nashville along the KY border.

South West USDA Hardiness Zones

The USDA Hardiness Zones for the South West are split into two groups. One covers areas in Texas along with parts of Oklahoma, New Mexico, and southwest Kansas. The other zone is further divided between California which includes southern Nevada up to the Lassen National Park area on one side and Oregon down to northern Baja, including Los Angeles County.

How to use your USDA hardiness zones

usda hardiness zones

Your USDA hardiness zones are numbers that help you determine which plants can survive the coldest winter temperatures in your area. The United States Department of Agriculture (USDA) has divided all of North America into 11 different zones based on their average annual low temperature and plant survival rates. Each zone represents an area where certain types of plants will usually grow well.

Your hardiness zone is determined by the average minimum temperature during winter months in your area, with each degree representing a horticultural or growing difference between two zones (for example, Zone 12 has an average annual low of -20 degrees F while Zone 13’s average low is -15 degrees).

Since USDA plant hardiness maps are based on average lows, you should also consider your geographic location within the zone to determine which plants are most likely to survive. For example, if you live in an area where temperatures fluctuate wildly between warm and cold each year depending on weather patterns, your plant hardiness may be different from that of a neighbor who lives across town or down the street.


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