Us climate zones for plants

Plant Hardiness Zone Map

The USDA created a standard to which gardeners can use to determine which plants can survive in which locations. This data is based on the average annual minimum winter temperature divided into 10 degree Fahrenheit zones. This map was created in 2012 and is a great guide for gardeners to use to decide what plants they can grow and survive through the winter.

At Plant Addicts we do our best to list the most accurate data on each plant page. So make sure you look to see which zones a plant can grow in before ordering. You can bend the guidelines somewhat by planting in more sheltered areas, or if you live in a micro-climate. But we recommend using the plant growing zones as your guide to decide what to plant outside.

If you are unsure what growing zone you are in, you can enter in your zip code in the tool at the top right of the website and it will tell you. Or you can tell from the map below too.

States in Growing Zone 1

Alaska

States in Growing Zone 2

Alaska

States in Growing Zone 3

Alaska, Colorado, Idaho, Maine, Minnesota, Montana, New Hampshire, New York, North Dakota, Vermont, Wisconsin, Wyoming

States in Growing Zone 4

States in Growing Zone 5

States in Growing Zone 6

States in Growing Zone 7

States in Growing Zone 8

States in Growing Zone 9

States in Growing Zone 10

Arizona, California, Florida, Hawaii, Louisiana, Nevada, Texas

States in Growing Zone 11

California, Florida, Hawaii

States in Growing Zone 12

Hawaii

States in Growing Zone 13

Hawaii

Plant hardiness zones—also known as planting zones or growing zones—help gardeners understand which plants can survive their region’s climate. Find out which planting zone you’re located in so that you can grow your best garden yet!

What Are Planting Zones?

When choosing perennial plants for your garden, it’s important to select varieties that can thrive year-round in your area, especially in regions where extreme winter temperatures are normal. Planting zones define, generally, which plants can survive winter in your area, and zones are typically listed in plant growing guides for reference.

The two most commonly referenced hardiness zone maps are those produced by the U.S. Department of Agriculture (USDA) and Natural Resources Canada (NRC). Different measures are used to create each country’s map, as explained below.

Zone maps are not absolute; if you find the information contradictory to your own experience, you may live in a microclimate. Soil, moisture, humidity, heat, wind, and other conditions also affect the viability of individual plants.

Find Your USDA Planting Zone

Considered the standard measure of plant hardiness, the USDA Plant Hardiness Zone Map is based on average annual minimum winter temperatures. The map is divided into thirteen distinct 10ºF zones, which are further divided into sub-zones of 5°F.

Check out the official USDA Plant Hardiness Zone Map below, then go to the USDA website to find out exaclty which zone you live in!


USDA Plant Hardiness Zones Map, 2012.

Note: The USDA Plant Hardiness Zone Map was last updated in January of 2012, the first update since 1990. About half of the country was made a half-zone warmer on the map. According to the USDA, the scientists are using a different set of long range data and more sophisticated computers for a more accurate map, especially in challenging areas such as mountain zones, which may have been rated too cold or warm in prior iterations of the map. Learn more about the updated map here.

How to Use Your Planting Zone

Planting zones are most useful to gardeners growing perennial plants, since perennials are meant to live beyond just one growing season. Perennials need to be able to survive winter in your area, so it’s important to know how cold it typically gets in your area and whether a particular plant is hardy enough to survive those temperatures.

Perennial flowers, shrubs, and trees grow best when planted in the appropriate zone. You’ll find that winter damage occurs most often when plants are out of their range or “comfort zone.” When you choose plants for a garden or landscape, avoid selecting plants that are only marginally hardy for your region; that’s when you’ll see winter damage, poor growth, and a reduction in flowering.

Planting native species is a surefire way to achieve a stable garden. See our article on natural landscaping.

For annual plants, like most vegetables and some flowers, it’s far more important to pay attention to things like the length of your growing season and the typical dates of your first and last frosts. (See local frost dates here.) Because annuals are only meant to last the length of one growing season, planting zones don’t necessarily factor into the equation.

NRC Canadian Planting Zones Map

Unlike the USDA map, which is based only on minimum winter temperatures, the planting zones map produced by Natural Resources Canada considers a wider range of climatic variables, including maximum temperatures and the length of the frost-free period. However, the NRC also produce a map that shows plant hardiness zones for Canada based on the USDA extreme minimum temperature approach. .

Check out a simplified version of the official Natural Resources Canada Plant Hardiness Zone Map below, then go to the Natural Resources Canada website to find out which zone you live in!


Natural Resources Canada Plant Hardiness Zones Map (simplified version), 2014.

Learn More

Another key part of successful gardening is knowing when your frost dates are. Find your local frost dates here.

What are your thoughts on planting zones? Are they accurate? Let us know in the comments below!

What is my climate zone?

Still in need of more information? Advice to Grow By – Ask Us HERE!

Buy map” title=”Generalized Plant Climate Map of California
Buy map” />Generalized Plant Climate Map of California
Buy map

Most gardening books, catalogs, and seed packets refer to plant hardiness zones, climate zones, or growing zones. Temperature hardiness climate zones are based on normally expected high and low temperatures and serve as guides to help you know which plants will grow where you live.

Temperature is not the only factor in figuring out whether a plant will survive in your garden. Soil types, rainfall, day length, wind, humidity, and heat also play their roles. Even within a city, a street, or a spot protected by a warm wall in your own garden, there may be microclimates that affect how plants grow. The zones are only a guide and a good starting point, but you still need to determine for yourself what will and won’t work in your garden.

Of 24 climate zones defined in the Sunset Western Garden Book and the 20 zones defined by the United States Department of Agriculture (USDA), California has 20 and 16, respectively.

The USDA plant hardiness map divides North America into 11 hardiness zones. Zone 1 is the coldest; zone 11 is the warmest. When you order plants from catalogs or read general garden books, you need to know your USDA zone in order to be able to interpret references correctly. The American Horticultural Society has also issued a Plant Heat-Zone Map.

Gardeners in the western United States sometimes are confused when confronted with the 11 Hardiness Zones created by the USDA, because we are used to a 24-zone climate system created by Sunset Magazine. The Sunset zone maps, considered the standard gardening references in the West, are more precise than the USDA’s, since they factor in not only winter minimum temperatures, but also summer highs, lengths of growing seasons, humidity, and rainfall patterns.

Climate Zone Info

WHAT IS PLANT HARDINESS

Do you love beautiful plants? I do, too! Let’s fill our gardens with the plants we love – won’t that be perfect? I’ll plant plumeria in Wisconsin, and you plant peonies in Florida!

WHY DOESN’T THAT WORK?

There are thousands upon thousands of plant varieties that thrive in the United States – but not every plant is happy in every single state. Kind of like how we have both polar bears and alligators, but the polar bears are just in Alaska, while the alligators are just in the coastal south east. Each lives in the climate and conditions to which they have adapted. Polar bears (and peonies!) actually need the cold and ice to survive, and could never live in the Florida swamps no matter how much the alligator might love it there. Plants are like that too. And the best way to make a plant happy is to mimic the conditions of its native habitat all year round.

While most plants will be happy in nearly any part of the country during the spring, some like peonies, need a bitterly cold winter to trigger their new growth and blooming for the following spring, and simply will fail to do either without it. Others cannot survive a freeze and will die if they do – like plumeria. So a plant is considered “hardy” where it can be planted in the ground and left to grow there all year long. It gets all of is climate related needs met by nature out in the garden.

WHAT ARE CLIMATE ZONES?

That is what plant hardiness and climate zones or growing zones are all about. The USDA divided the entire United States into climate zones to help gardeners to determine what plants would thrive in their gardens. You typically see a map of the United States colored in according to their zones like the one above.And we have this handy tool here, where you can just enter your zip code to learn your climate zone. What climate zone am I in?

  • Shop Climate Zone 3
  • Shop Climate Zone 4
  • Shop Climate Zone 5
  • Shop Climate Zone 6
  • Shop Climate Zone 7
  • Shop Climate Zone 8
  • Shop Climate Zone 9
  • Shop Climate Zone 10
  • Shop Climate Zone 11

Climate zones are determined by the coldest average winter temperature the geographical area typically experiences. You can see the coldest temps and their zones here, further divided into A (colder half of the zone) and B (warmer half of the zone).

So if you live in St. Louis Missouri, and your average coldest winter temperature is -5 degrees Fahrenheit, you can see from this chart that you live and garden in zone 6. So plants and bulbs that need a seriously cold winter in order to survive and bloom and thrive, like most tulips, peonies, snowdrops or cherry trees, will do well in your garden. And those plants that will be harmed or killed by a freeze either should not be planted at all or should be brought indoors over the winter or treated like annuals.

Now that you know what climate zone you are in, you can use this information to make great choices for planting your garden. Plants are listed as hardy to a range of zones, like Narcissus Grand Primo is hardy in zones 6-10, and Allium Atropurpureum is hardy in zones 4-8. If you garden in zone 6, both of these varieties would thrive for you, because zone 6 is within the hardiness range of both plants! But if you garden in zone 5 or zone 9, only one of these two would work for you. Fortunately, there is a myriad of beauty that will thrive in every climate! And now you have the tools for determining which is right for you.

So – now that you know your climate zone and what it means and how to use it, does this mean you can never enjoy frost tender perennials like freesias or dahlias in your cold winter garden? Wouldn’t that be too sad? You absolutely can plant and grow varieties that are not cold hardy in your climate – it just takes extra work to get the same great results, as you make up for the qualities the plant needs that your climate lacks!

In cold winter climates, plant tender bulbs and plants in the spring, so they grow, flower and go dormant before autumn turns cold. Then either bring them indoors or treat them as annuals. For mild winter climate gardeners who dearly love classic tulips and snowdrops, plant to pre-chill them for many weeks (10-12) before setting them outside in January or February. This way, you simulate the colder winter they need.

Explore the wild world of beautiful plants that do thrive in your climate. And for the one your heart craves that your climate doesn’t suit – I’ll bet it is worth the effort! 🙂

Happy Gardening!

Leave a Reply

Your email address will not be published. Required fields are marked *