The Plant Hardiness Zone Map was updated for the 2024 gardening season with the addition of thousands more local weather stations. Look at your growing zone or gardening zone to understand which plants can survive your area’s climate. Did your planting zone change?
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 generally define 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 current standard measure of plant hardiness, the USDA 2023 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 subzones of 5°F.
Check the official USDA Plant Hardiness Zone Map below, or visit the USDA website to find out exactly which zone you live in!
Plant Zone Map Courtesy of USDA
Note: The USDA Plant Hardiness Zone Map was just updated in November 2023, the first update since 2012. According to the USDA, the new 2023 map uses data from 13,412 weather stations compared to 7,983 from the previous map. Compared to the 2012 map, the 2023 version shows that half of the country moved up to a warmer zone (including much of Alaska) while the other half stayed in the same zone.
The scientists are using 30 years of long-range data and more sophisticated computers for a more accurate map, especially in challenging areas such as mountain zones and Alaska, which may have been rated too cold or warm in prior map iterations. Learn more about the updated map here.
How to Use Your Planting Zone
Planting zones are most helpful to gardeners growing perennial plants since they live beyond just one growing season, regrowing each spring. Perennials need to be able to survive winter in your area, so it’s essential 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.
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 produces a map that shows plant hardiness zones for Canada based on the USDA extreme minimum temperature approach. Click here to see both Canadian planting zone maps.
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!
I am a first year gardener and I am having a hard time determining my zone. Reason being we get Temps as low as -16F but as high as 116F. I thought I was in 2 ...but...I can't find anything on that so. Trying to determine what kind of edible trees I can grow, but...anyone offer some help? Thanks!!
My zone Rocky Ford Colorado is listed as a 5b.. which is -15 below and it's not hadsn't been for many years.. I lost everything my first winter here at 35 below winter temps.. on average we get -25 below winter temps every year..we treat our backyard perrennials as zone 4 when planting.. I've had more success planting for a colder winter.. My whole espalier orchard is zone 3 and 4.. You need to rethink and recalculate growing zones .. most are no longer ACCURATE
The wind chill has little or no affect on plants.
Copied from Horticulture News Letter:
Wind chill does not affect plants, as they respond to the actual air temperature and do not generate heat that can be pulled away by wind. However, wind itself can dry out stems and foliage and result in damage, especially in winter when the air is already relatively dry. Wind chill combined with below freezing temperatures may cause problems in a few hardy plant stems and leaves, but it is not enough to kill a hardy plant.
link - https://www.hortmag.com/headline/what-wind-chill-means-for-plants
Hello everyone I have tried really hard scanning this page for what zone is where and I still don't see the way to do that --can somebody please help me how to do this?
Just Google type in your city and state and grow zones..
Mine I would be Rocky Ford Colorado grow zones.. comes 5b but it's colder we plant for zone 4 and below