Gardening Zones: What To Plant in US Plant Hardiness Zones By Season, Type

Georgette Kilgore headshot, wearing 8 Billion Trees shirt with forest in the background.Written by Georgette Kilgore

Gardening | February 21, 2024

Woman looking at giant gardening zones map to figure out which plants flourish in US hardiness zones by season, and how to choose plants for your growing zone.

Cultivating the green thumb that will grow you the perfect garden means educating yourself on several elements, like gardening zones, that go into creating a plant-friendly space.

And remember, you don’t want to simply keep plants alive, you want them to thrive.

Familiarizing yourself with the plants best suited to your particular climate is one of the most important things to learn.

This guide to the U.S. Hardiness Zones Map will be a key resource for determining such plants for home gardens and gardening zones, so you’ll know which plants will survive all seasons and which ones will need to be planted in containers that can be moved indoors of the temperatures become too extreme for them.

What Are Gardening Zones?

The United States Department of Agriculture (USDA) gardening zones map divides the United States into 13 climate zones based on the average low temperatures of each region.

Zones are divided into 10-degree increments and were originally designed to help farmers determine the appropriate crops to grow in their climate. But it has become a handy tool for the home gardener as well.

Graphics of gardening zones showing its benefits which include determining the best time to plant and growing healthier plants and limitations of the information from the USDA hardiness zone map which include topography, microclimate, and general weather condition.

While there are 13 climate zones in the country, almost all of the continental United States falls into zones 3 to 10, except one region of Northern Minnesota. The zones go from coldest to hottest, meaning zone 1 has the most frigid temperatures, and zone 13 has the warmest.

In a nutshell, this map helps you identify which plants will survive the winter temperatures in your area. The cold affects plants in numerous ways, so knowing which ones can withstand the average lows in your area is key to a thriving outdoor space.

The current hardiness zone map was created in 2012, drawing on climate data collected from 1976 through 2005.

As you can see, the guidelines were created by determining average temperatures over a long period of time and not just noting the lowest temperature ever recorded in each region. This version is the first map you can access on the internet.


All zones have two subzones divided into 5-degree increments. They will be labeled ‘A’ and ‘B.’ For example, Zone 7A and B.

While a 5-degree difference may not sound like much, it can make all the difference in creating a garden full of prospering plant life.

You can determine your zone and subzone by visiting the USDA site,2 where you can view the maps and enter your zip code.

Many plants in nurseries and the like may not include the subzone on the label, only the general zone. So be sure to do your research or ask the staff at the gardening center for guidance.

Gardening Zones Map and When To Plant

The information provided by the hardiness maps helps determine when to plant things meant to last over the long term, such as perennial flowers, trees, shrubs, and ground cover.

For these garden elements, planting typically takes place in the spring after the final frost, and before the appearance of the first one later in the year. So, the planting recommendations usually focus on this broader period, letting you know the earliest you can start planting for that season.

Some plants, however, can be planted in the fall, and it is best to research the individual plants you want to include in your garden to get more specific information.

There are some things to keep in mind about the frost period:3

  • The given dates for any zone are not set in stone. They are an estimate based on historical data taken over a sustained period.
    There may be a 30 percent chance of the first frost date occurring before the given time or the last frost occurring after the stated time.
  • Frost tends to show up when the temperature reaches 32 degrees but may also form at just above-freezing temperatures.
  • Other factors influencing frost formation include microclimates, topography, and the general weather.
  • Because frost dates are not set in stone, regularly monitor the weather forecast before you begin planting.

Because of the map’s limitations, and the unique elements of different plants, it is important to do your homework on any plants you plan on putting in your garden.

For example, some plants may do well being planted as early as possible in the growing season as they may be more fragile in their earlier stages,9 and less likely to survive if they were to start growing in the dead of summer.

The USDA zones will take you a long way in planning for gardening success, but it’s not the only information to rely on in making your plans.

Zone 1: Temperature Average and Area

Zone 1 covers areas with minimum temperatures below -50 degrees Fahrenheit, and unless you live in Fairbanks or a handful of other areas of Alaska, you needn’t worry about finding plants that can survive such frigid weather.

Zone 1 areas generally have a lot of wildlife that will be all too happy to feast on your plants, so you might need fencing and other protective measures.

Graphic of best plants to grow in Zone 1 showing the US map with prevailing temperature range in Zone 1 and images of some of the species best for garden planting which include broccoli, radish, Brussels sprouts, cabbage, Lily of the valley, Siberian iris, yarrow, columbine, Delphinium, chives, Oxeye daisy, and coltsfoot.

While natural plants naturally thrive the best and should be an important part of your garden no matter the region, the extremely harsh conditions of this zone make it particularly prudent to focus heavily on native flora.

In addition to the ability to withstand extreme cold, many plants suited for Zone 1 have a high drought tolerance.

Growing Season and Good Plants for This Zone

This zone has a very short growing season, with the last frost typically occurring in early June and the first frost as soon as the last week in August! Because of such a short season, you may find it advantageous to grow some plants indoors and transfer them outside once planting season begins.

  • Lily of the Valley
  • Siberian Iris
  • Yarrow
  • Columbine
  • Cranesville
  • False Spirea
  • Creeping Jenny
  • Delphinium
  • Dwarf Birch
  • Netleaf Willow
  • Artesmia
  • Cotton Grass
  • Coltsfoot
  • Golden Rod
  • Arrowhead
  • Sheep Sorrel
  • Oxeye Daisy
  • Selfheal
  • Broccoli
  • Brussels Sprouts
  • Cabbage
  • Dill
  • Radish
  • Chives

Zone 2: Temperature Range and Area

Zone 2 covers areas with minimum temperatures between -50 degrees Fahrenheit and -40 degrees Fahrenheit.

Graphic of best plants to grow in Zone 2 showing the US map with prevailing temperature range in Zone 2 and images of onions, carrots, okra, Paper birch, Bog rosemary, Juniper, Lady's Slipper orchid, American basswood, White spruce, and Nanking cherry.

It mainly refers to areas in Alaska, but also the northernmost part of Minnesota. While a bit warmer than zone 1, you are still dealing with pretty punishing temperatures.

Native plants will again be the best bet.

Growing Season and Good Plants for This Zone

The last frost typically occurs in the second or third week of May, with the first frost beginning sometime during the first week of September.

  • Iceland Poppy
  • Bog Rosemary
  • Leadplant
  • Serviceberry
  • American Cranberry Bush
  • American Basswood
  • White Spruce
  • Paperbirch
  • Juniper
  • Nanking Cherry
  • Drumstick Primula
  • Creeping Phlox
  • Lady’s Slipper Orchid
  • Okra
  • Love-Lies-Bleeding plant
  • Blue-Bleed Lily
  • Black and White Minstrels
  • Viola Blanda
  • Carrots
  • Onions
  • Viola palustris

Zone 3: Average Temperature and Area

The average minimum temperatures in zone 3 fall between -40 degrees Fahrenheit and -30 degrees Fahrenheit.

Zone 3 includes the coldest parts of the continental US, such as certain areas of Wisconsin, Minnesota, North Dakota, Montana, and Maine.

Graphic of best plants to grow in Zone 3 showing the US map with prevailing temperature range in Zone 3 and images of asparagus, cucumbers, garlic, celery, chard, hosta, bergenia, hollyhock, tulips, Asiatic lilies, and Red maple.

Most native plants fall into zone 3 through 10, so being at the beginning of this range means you have plenty of options.

Growing Season and Good Plants for Zone 3

The last frost typically occurs sometime in the first two weeks of May and the first frost during the second week of September.

  • Siberian Bugloss
  • Lady Fern
  • Hosta
  • Bergenia
  • Hollyhock
  • Tulips
  • Squash
  • Garlic
  • Parsley
  • Mint
  • Red Maple
  • Sweet Birch
  • Fringetree
  • Zinnia
  • Petunia
  • Marigold
  • Day Lily
  • Blackhaw
  • Ferns
  • Rockfoil
  • Lady’s Mantle
  • Snowdrop
  • Asiatic Lilies
  • Daisies
  • Grape Hyacinth
  • Heliopsis
  • Liatris
  • Maltese Cross
  • Asparagus
  • Cucumbers
  • Garlic
  • Aster
  • Dill
  • Celery
  • Bergamot
  • Sprouts
  • Parsley
  • Celery
  • Cabbage
  • Chard
  • Broccoli

Zone 4: Average Temperature and Area

Zone 4 minimum temperatures range from -30 degrees Fahrenheit to -20 degrees Fahrenheit. So while it’s starting to warm up a bit, plants in this zone will still be exposed to temperatures well below freezing.

Graphic of best plants to grow in Zone 4 showing the US map with prevailing temperature range in Zone 4 and images of thyme, cucumbers, sage, pumpkin, cosmos, sunflower, lupine, coneflower, azalea, eggplant, and barberry.

This zone includes sections of Alaska, Montana, Wisconsin, North Dakota, Maine, South Dakota, Idaho, Colorado, Nebraska, Iowa, New York, New Hampshire, and Vermont.

Growing Season and Good Plants for This Zone

Zone 4 areas typically experience the last frost anywhere from the last week of April through the first two weeks of May, with the first frost starting anywhere from the end of September through the first week in October.

  • American Mountain Ash
  • Eastern White Pine
  • Red Maple
  • Cosmos
  • Sunflower
  • Nasturtium
  • Lupine
  • Coneflower
  • Floral Bells
  • Black Chokeberry
  • Bottlebrush Buckeye
  • Red Twig Dogwood
  • Lemon Balm
  • Thyme
  • Sage
  • Eggplant
  • Pumpkin
  • Bugleweed
  • Bloodroot
  • Trumpet Gentian
  • Shasta Daisies
  • Rockcrest
  • Gayfeather
  • Violets
  • Barberry
  • Azalea
  • Eggplant
  • Pumpkin
  • Asparagus
  • Arugula
  • Gourds
  • Rhubarb
  • Orach
  • Lettuce

Zone 5: Average Temperature and Area

Zone 5 has minimum temperatures between -20 degrees Fahrenheit and -10 degrees Fahrenheit.

Graphic of best plants to grow in Zone 5 showing the US map with prevailing temperature range in Zone 5 and images of peony, poppy, lavender, sedum, echinacea, bee balm, hellebore, foxglove, kale, and oregano.

Zone 5 includes mid-Atlantic states such as New York, New Jersey, Pennsylvania, and West Virginia; part of the northern Central US such as Iowas and Nebraska, and out to parts of Montana, Wyoming, Northern California, Washington, Oregon, and Idaho.1 It also includes parts of Alaska, Nevada, and Colorado.

Growing Season and Good Plants for This Zone

With Zone 5 you are moving into a bit longer of a growing season, with the last frost ending anywhere from the second to last week in April, and the first frost beginning sometime in mid-October.

  • Butterfly Weed
  • Peony
  • Hollyhock
  • Salvia
  • Poppy
  • Lavender
  • Lilies
  • Sedum
  • Echinacea
  • Bee Balm
  • Russian Sage
  • Jacob’s Ladder
  • Hellebore
  • Foxglove
  • Monkshood
  • Spiderwort
  • Balloon Flower
  • Pink Oak
  • River Birch
  • Butterfly Bush
  • Ninebark
  • Black-eyed Susan
  • Impatiens
  • Verbena
  • Roses
  • Mums
  • Lettuce
  • Radishes
  • Kale
  • Oregano
  • Thyme
  • Rosemary
  • Spinach
  • Honeycrisp Apples
  • Corn
  • Echinacea
  • Mint
  • Onion
  • Wildflowers
  • Sage

Zone 6: Average Temperature and Area

Zone 6 has minimum temperatures from -10 degrees Fahrenheit to 0 degrees Fahrenheit.

Graphic of best plants to grow in Zone 6 showing the US map with prevailing temperature range in Zone 6 and images of coriander, boxwood, Rhododendrons, Anise hyssop, geranium, tomato, pepper, hydrangea, and cantaloupe.

Zone 6 includes parts of the mid-Atlantic states such as New York and New Jersey, then extends down to Maryland, Washington D.C., North Carolina, and some of Georgia. This zone also covers areas in the Midwest such as Kansas, Ohio, and Kentucky, temperate southwest regions in Utah, Colorado, New Mexico, and Arizona as well as the Pacific Northwest.

Finally, it covers certain areas of New Hampshire, Massachusetts, Maine, and Alaska.

Growing Season and Good Plants for This Zone

In Zone 6 areas, the last frost typically occurs sometime within the first 3 weeks of April, with the first frost sometime in the last two weeks of October.

  • Formosa Lily
  • Konjac
  • English Lavender
  • Sweetgum
  • Eastern Redbud
  • Kousa Dogwood
  • Petunia
  • Geranium
  • Salvia
  • Rose of Sharon
  • Japanese Spirea
  • Boxwood
  • Tomatoes
  • Squash
  • Peppers
  • Cucumbers
  • Hydrangea
  • Rhododendrons
  • Azalea
  • Forsyth
  • Butterfly Bush
  • Anise Hyssop
  • Goat’s Beard
  • Wild Ginger
  • Milkweed
  • Squash
  • Butter Lettuce
  • Oregano
  • Coriander
  • Cantaloupe
  • Cilantro
  • Peppers

Zone 7: Average Temperature and Area

Zone 7 winter temperatures average 0 degrees Fahrenheit to 10 degrees Fahrenheit.

Graphic of best plants to grow in Zone 7 showing the US map with prevailing temperature range in Zone 7 and images of turnips, Calla lily, snapdragon, begonia, camellia, strawberry, forget-me-not, squash, and zucchini.

Zone 7 areas include parts of New Mexico, most of Tennessee, southern Oklahoma, Delaware, Maryland, Virginia, western North Carolina, northern Texas, Georgia, Alabama, Arkansas, and Mississippi.

Growing Season and Good Plants for This Zone

In Zone 7, the last frost usually occurs anywhere from the last week in March to the first few days of April, with the first frost typically occurring at the very end of October through the first two weeks of November.

  • Conifers
  • Golden Mops
  • Abelia
  • Camellia
  • Heuchera
  • Barrenwort
  • Lavender
  • Calamintha
  • Lenten Rose
  • Lilyturf
  • Dianthus
  • Coral Bark Maple
  • Oakleaf Hydrangea
  • Burning Bush
  • Dogwood
  • Southern Magnolia
  • Pink Oak
  • Yoshino Cherry
  • Begonia
  • Snapdragon
  • Coleus
  • Crape Myrtle
  • Canna Lily
  • Calla Lily
  • Arugula
  • Squash
  • Sage
  • Tarragon
  • Turnips
  • Arugula
  • Forget-Me-Nots
  • Zucchini
  • Squash
  • Strawberry

Zone 8: Average Temperature and Area

Zone 8 average minimum temperatures range from 10 degrees Fahrenheit to 20 degrees Fahrenheit.

Graphic of best plants to grow in Zone 8 showing the US map with prevailing temperature range in Zone 8 and images of melon, rosemary, birds of paradise, begonia, Beavertail cactus, dahlias, Angel's trumpets, marigold, vinca, and lantana.

Zone 8 includes most parts of North Carolina, South Carolina, Georgia, Mississippi, Alabama, Florida, Louisiana, Arkansas, Texas, Arizona, and California, coastal areas of Oregon and Washington, and small sections of Nevada, Utah, New Mexico, and Hawaii.

Growing Season and Good Plants for This Zone

The last frost in Zone 8 usually occurs sometime within the last two weeks in March, with the first frost occurring sometime from the second week of November through the first day in December.

  • Purple Arrowroot
  • Lily of the Nile
  • Beavertail Cactus
  • Dahlias
  • Angel’s Trumpets
  • Marigold
  • Vinca
  • Lantana
  • Lavender
  • Oleander
  • Indian Hawthorn
  • Southern Live Oak
  • Red Maple
  • Bald Cypress
  • Rosemary
  • Sage
  • Oregano
  • Tomatoes
  • Peppers
  • Melons
  • Birds of Paradise
  • Hibiscus
  • Christmas Cactus
  • Citrus Trees
  • Nut Trees
  • Apple Trees
  • Fig Trees
  • Okra
  • Collards
  • Eggplants
  • Mustard
  • Squash

Zone 9: Average Temperature and Area

The average winter temperatures in Zone 9 span from 20 to 30 degrees Fahrenheit.

Graphic of best plants to grow in Zone 9 showing the US map with prevailing temperature range in Zone 9 and images of Bay laurel, basil, peanut, artichoke, butterfly bush, rudbeckia, Hardy hibiscus, Silver wattle, Crape myrtle, and Kangaroo paw.

Zone 9 includes parts of Georgia, Florida, South Carolina, Texas, Alabama, Mississippi, Louisiana, Utah, New Mexico, Arizona, Nevada, California, Washington, Oregon, and Hawaii.

Growing Season and Good Plants for This Zone

The last frost in Zone 9 usually occurs anywhere from the start of the second week of February through the end of the month, with the last frost anywhere from the last week of November through mid-December.

  • Bluebeard
  • English Lavender
  • Hummingbird Mint
  • Butterfly Bush
  • Rudbeckia
  • Gayfeather
  • Mountain Marigold
  • Hardy Hibiscus
  • Silver Wattle
  • Pineapple Guava
  • Crape Myrtle
  • Mexican Sage
  • Kangaroo Paw
  • Zinnia
  • Madagascar Periwinkle
  • Angelonia
  • Bay Laurel
  • Basil
  • Cabbage
  • Peanuts
  • Shasta Daisy
  • Russian Sage
  • Lovegrass
  • Mandarin Oranges
  • Artichoke
  • Tomatillo

Zone 10: Average Temperature and Area

Zone ten average low temperatures range from 30 to 40 degrees Fahrenheit. This zone refers to areas of southern California, southern Florida, Hawaii, and the southernmost tip of Texas.

Graphic of best plants to grow in Zone 10 showing the US map with prevailing temperature range in Zone 10 and images of bromeliads, bougainvillea, beets, papaya, aloe vera, queen of the night, California poppy, gazania, agapanthus, and orchids.

Naturally tropical plants will thrive well here, but many cold-hardy plants would not survive these temperatures.

Growing Season and Good Plants for This Zone

Zone 10 has an extremely long growing season as the last frost typically occurs mid-to-late January and the first frost occurs mid-to-late December.

  • Aloe Vera
  • Queen of the Night
  • California Poppies
  • Wax Begonia
  • Sunflower
  • Gazania
  • Agapanthus
  • Bird of Paradise
  • Bromeliads
  • Oleander
  • Bougainvillea
  • Monkey Puzzle
  • Strawberry Tree
  • Royal Poinciana
  • Azaleas
  • Beets
  • Orchids
  • Papaya
  • Petunias
  • Verbena
  • Watermelon
  • Tango Hummingbird Mint
  • Shaw’s Agave
  • Beautyberry
  • Epazote
  • Melon
  • Zucchini

Zone 11: Average Temperature and Area

The average low temperatures in Zone 11 fall between 40 degrees Fahrenheit and 50 degrees Fahrenheit.

Graphic of best plants to grow in Zone 11 showing the US map with prevailing temperature range in Zone 11 and images of Coconut palm, Pineapple plant, lemongrass, Fiddle Leaf fig, Mango, cosmos, ginger, Heliconia, Elephant's ear, Plumeria, and lemon.

This zone encompasses the Florida Keys, parts of Puerto Rico, and most of the Big Island of Hawaii.

Growing Season and Good Plants for This Zone

Zone 11 has zero frost so you can grow all year long.

  • Torenia
  • Cosmos
  • Ginger
  • Heliconia
  • Elephant’s Ear
  • Plumeria
  • Ti Plant
  • Gumbo Limbo
  • Orchid Tree
  • Coconut Palm
  • Lantana
  • Scarlet Star
  • Pineapple Plant
  • Flamingo Flower
  • Kale
  • Swiss Chard
  • Lemongrass
  • Mangos
  • Limes
  • Lemons
  • Peace Lily
  • Money Tree
  • Ponytail Palm
  • Burgundy Rubber Tree
  • Swiss Cheese Monstera
  • Fiddle Leaf Fig
  • Beets
  • Mangos
  • Begonias
  • Chives

Zone 12: Average Temperature and Area

Zone 12 low temperatures average between 50 degrees Fahrenheit and 60 degrees Fahrenheit. This zone is exclusive to parts of Hawaii and Puerto Rico.

Graphic of best plants to grow in Zone 12 showing the US map with prevailing temperature range in Zone 12 and images of Avocado tree, Papaya tree, Weeping fig, eggplant, hot pepper, hibiscus, bougainvillea, Sunsugar Orange Cherry tomato, Angel Wing begonia, borage, String of Pearls, and Blue ginger.

With such warm weather year-round, this zone is home to many exotic plants you will not see in the continental US. And because of such warm weather, many plants grown there can’t be grown here.

Growing Season and Good Plants for This Zone

With temperatures this high, there is no frost season, allowing you to putter around your garden all year round.

  • Avocado Tree
  • Papaya Tree
  • Flamboyant Tree
  • Soft Tree Fern
  • Weeping Fig
  • Plumeria
  • Hibiscus
  • Bougainvillea
  • Foxtail Orchids
  • Blue Ginger
  • Sea Purslane
  • Eggplant
  • Peppers
  • String of Pearls
  • Cardinal Climber
  • Grande Verde Rio Tomatillo
  • Sunsugar Orange Cherry Tomato
  • Angel Wing Begonia
  • Hot Pepper
  • Borage

Zone 13: Average Temperature and Area

In Zone 13, the average winter temperatures are above 60 degrees Fahrenheit.

Graphic of best plants to grow in Zone 13 showing the US map with prevailing temperature range in Zone 13 and images of Banana tree, Coconut palm, bamboo, acacia, Moth orchids, Cattleya orchids, rosemary, crotons, Heliconia, African breadfruit.

And like Zone 12, it only include areas of Hawaii and Puerto Rico.

Growing Season and Good Plants for This Zone

It’s open season all year long as far as tending your garden goes.

  • Coconut Palm
  • King Palm
  • Banana Trees
  • Moth Orchids
  • Cattleya Orchids
  • Crotons
  • Bamboo
  • Bird of Paradise
  • Heliconia
  • African Breadfruit
  • Triangle Palm
  • Queen Palm
  • Amazon tree-grape
  • Acacia
  • Rosemary
  • Bush Beans

How Was the Map Created?

In 1927 the Arnold Arboretum created the first hardiness zones map.4 It consisted of 8 zones and was updated several times over the next few decades.

The USDA created its first map in 1960, using dates from 450 weather stations around the country. The USDA map and the Arnold Arboretum map used different criteria for determining the zones and had a lot of conflicting information.

The Arnold Arboretum map remained the standard until 1990, when the USDA joined with the US National Arboretum to update the maps, gathering data from thousands of weather stations over more than the course of a decade. This map moved most locations half a zone to one zone cooler than the Arnold map.

Why Is It Important To Know Garden Planting Growing Zones (USDA Zones)?

A lot goes into creating a beautiful garden. Knowing the growing zones is particularly important because while several factors determine the best plants for a particular region,5 temperature will exert the most influence.

And because of the importance of temperature, the hardiness zone ratings are a great starting point for determining which plants are most likely to live a long, healthy life in your neck of the woods.

Nothing will be more discouraging than spending a lot of money on plants and spending lots of time lovingly tending to them, only to have them die because it is simply too cold for them to survive. This vital information will help you plan your garden more precisely and efficiently.

Helpful Supplements to the Planting Zone Map

Here are additional types of maps that will help you gather more information about the gardening zones in the US.

Heat Zone Maps

Cold has the potential to seriously damage plants.

So, the planting zone map provides crucial information for farmers and gardeners. But heat can be equally damaging to many plants.

If a plant can withstand temperatures of -10 degrees Fahrenheit, it stands to reason it would do fine in a warmer zone with an average low of 20 degrees Fahrenheit.

But at some point, an area’s average maximum temperatures may factor in, meaning this plant could not thrive there no matter how well it could withstand the colder part of the year. This part of the puzzle is where the heat zone map comes in.

Created in 1997 by the American Horticultural Society, heat zone maps are helpful for people living in regions where warmer weather will play a more involved role in choosing appropriate plants.6

The map divides the country into 12 zones based on the number of days each year the temperature rises above 86 degrees, the point at which most plants experience heat stress. More and more plants have labels with their heat zone number, which indicates the highest temperatures they can withstand.

This map does have its limits though, as it doesn’t contain data many would consider important, alongside the general temperature, such as humidity levels, average rainfall, and evening temperatures.

Sunset Climate Maps

These maps take into account numerous climate factors to more precisely plan your garden.7

  • Latitude

The further away an area is from the equator, the shorter its days. How much sun an area gets will influence which plants are best for it.

  • Elevation

If you live at a higher elevation, your winters will be colder and longer, than lower elevation areas in your same zone. Your garden will experience more intense sunlight and lower temperatures in the evening.

  • Ocean Influence

Gardening in the coastal areas may come with challenges that more inland areas in your USDA zone won’t have, such as higher winds and salt in the air.

  • Mountains, Hills, and Valleys

Topography has a significant influence on planning your garden. Interior mountains near coastal areas will reduce the effects of the ocean.

Mountain ranges can protect the areas between them from the harsher weather conditions that occur there.

  • Microclimates

The local landscape may create many microclimates within the same zone.

North-facing slopes will get more heat than those facing south. Hilltops are colder than hillsides.

What Are the Effects of Cold Weather on Plants?

Cold weather affects plants in many ways, and some plants can withstand these effects better than others.

In some cases, the cold weather may even help the plant. Some of these effects are:

  • Frozen water inside the plant’s cells causes it to expand, destroying it from the inside
  • Water can freeze the exterior of the plant and the surrounding soil, cutting off its water supply
  • Cold weather interrupts enzyme activities, reducing the plant’s ability to process nutrients

Hardiness Zone Map Considerations and Limitations

The Hardiness Zone map is very helpful to gardeners. However, it is not comprehensive and has its limitations

Calculating the Temperature Ranges of Gardening Zones

One factor contributing to the map’s limitations is the lack of information about how frequently the zone hit the lower end of the temperature range and how long it stayed that cold.

Not taking this information into account means a plant’s rating may not be accurate in that it may be able to survive that temperature for a short period of a few days, but it could not do so for several weeks, or more than one period during the season.


Just like certain geographic regions often have larger microclimates, you can also find smaller ones within your garden.8

So in addition to considering whether a plant is appropriate for your zone, consider other elements it needs to prosper, and if your outdoor space provides these optimal growing conditions. Because of the microclimates within your garden, you will have different plants in large, open sunnier areas, compared to areas with more shade.

A north-facing garden will be much colder than one facing east or south. A space may be colder if obstructed by your house or other structures, like a wall.

An area of your garden near a heating vent will be warmer. The climate is different in an area near a pond, bog, or creek, compared to areas away from the water source

A large boulder absorbs heat and raises the temperature of the ground around it. The soil in low spots will have more moisture.

Sloping land can be hotter or colder depending on how the sun hits them.

It Isn’t Just About Average Winter Temperatures

When looking at the map, where the zones stretch out from east to west, you quickly see many of the zones cover a diverse range of US locales, climate-wise. A garden in Raleigh, North Carolina will probably look pretty different than one in Reno, Nevada, which both fall into the same winter temperature zone, but have very different summers.

Because you can often use a plant from a colder zone in a warmer one, you typically see an overlap of recommended plants between zones. But in determining the optimal plants for your garden, you must also think beyond the winter temperature zones, to factors like humidity levels, soil conditions, and how much sun your area gets, to name a few.

So all of this is to say a plant that thrives in a particular minimum temperature won’t automatically do well anywhere less cold.

Summer heat causes changes in the plants that may increase their hardiness during cold weather. This means a plant in an area with hot summers may be able to withstand colder temperatures better than the same plant in an area that doesn’t have hot summers.

Warmer Plants in Colder Climates

While you can often plant something designed for a colder climate in a warmer one, can it ever be the other way around? Generally speaking, the answer is no. However, a plant meant for a warmer climate won’t automatically die in colder weather without question.

But because it won’t thrive as well as it could in proper conditions, it will probably lack many qualities you find appealing, whether its vibrant color or lush leaves.

Are the US Gardening Zones More Accurate in Certain Areas Than Others?

While the gardening zone maps have a variety of limitations, as noted above, where you live in the US may be a particularly important factor in determining how well you can rely on it.

Precipitation and higher elevation significantly influence how well plants thrive in a particular area.

The importance of these climate elements means assessments relying primarily on temperature won’t be as accurate for the many parts of the country, such as the Northwest and Mountain West. But if you live in the eastern half of the country, which is generally flatter and has less rain, the hardiness zone factor alone will be pretty good at predicting which plants are best for your space.

Whether you are looking for trees, shrubs, flowers, fruits, or vegetables, no matter the zone in which you live, abundant options are available to you.

While you can’t rely on the USDA gardening zones alone to decide what plants are best suited for your area, the degree of influence the cold has on plant life means this map is a great starting point for narrowing down your options.

Read More About Gardening Zones


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2US Department of Agriculture. (2023, March 10). USDA Plant Hardiness Zone Map. USDA Agricultural Research Service. Retrieved October 2, 2023, from <>

3US Dept of Commerce, National Oceanic and Atmospheric Administration, & National Weather Service. (2022, September 25). Frost and Freeze Information. National Weather Service. Retrieved October 2, 2023, from <>

4Pearson, L. (2023, July 1). Mapping an “Indeterminable Quantity”. Arnold Arboretum. Retrieved October 2, 2023, from <>

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9Environmental Protection Agency. (2023, July 21). Climate Change Indicators: Length of Growing Season. EPA. Retrieved October 2, 2023, from <>