Home gardeners and nursery owners can useiness zones to find out what plants will do well in certain areas.The map has been updated many times over the years.Several areas experienced a zone change due to the availability of more accurate data.
Step 1: Understand what a plant hardiness zone is.
Regional temperature averages are used to create hardiness zones.The difference between one band and the next is 10 degrees.The subzone a is 5 degrees cooler than the sub zone b.The official zone is the lowest or highest possible temperature in the area during a normal year.
Step 2: To find the recommended planting zone, check plant tags.
Gardeners should check plant tags and buy plants that are suitable for their zone.A perennial that is classified as being for zones 8 to 10 wouldn't survive the winter in zone 6.Gardeners in zone 11 would have a hard time getting the plant through the summer.
Step 3: Understand the issues with the plant scale.
The map is not perfect, but it is a good guide.Though efforts have been made to incorporate known microclimates into the updated map, the revised edition may not account for all of the nuances that are out there.Gardeners who are experiencing cold or warm periods may experience some plant loss as a result of the plant's inability to take into account extreme weather patterns.Some specimen that are said to grow in their zone may not thrive there.There are many factors besides temperature that may account for a perennial's success or failure.
Step 4: The USDA zone map can be used to find your plant's hardiness zone.
The USDA Hardiness Zone Map can help you determine your exact zone.Click on your state on the website.A detailed map of the state that includes major cities will show you where you live.To make this map, the USDA gathered average low winter temperature data for all areas throughout the United States and then grouped areas with similar temperatures together to form zones.The zones are cooler than the ones next to them.The USDA Hardiness Zone 5 is assigned to areas where the average winter low is between -20 and -10 degrees F.The USDA Hardiness Zone 4 is assigned to areas where the average winter low is between -30 and -20 degrees F.The zones are divided into 5 degrees.The USDA Hardiness Zone 5A winter lows are between -20 and -15 degrees Fahrenheit.
Step 5: The temperature scale is familiar to you.
The USDA Plant Hardiness Zone map shows the average annual minimum winter temperatures for each zone.
Step 6: Take the plant's heat tolerance into account.
It's important to consider the average high summer temperatures when determining which plants will grow in your zone.Plants can't take the heat in the south.When a plant is assigned a zone range, this high end of the plant's temperature tolerance is taken into account.The Japanese spirea is hardy in USDA Hardiness Zones 4 to 8.It will only thrive in climates where winter temperatures plummet.It won't grow well in the mild winters and hot summers of USDA Hardiness Zone 9.
Step 7: If you live in a microclimate, consider it.
Living in warmer climates in the west, south and along the coast can make finding your gardening zone a little more difficult.The areas have microclimates that are influenced by elevation.The temperatures in these microclimates aren't the norm for the general area.In order to help gardeners purchase the right plants, Sunset Magazine has gathered information about the microclimates.Simply enter your zip code when you click on "What is your Sunset Climate Zone?" on the "Plant Finder" page.Sunset climate zone tolerances aren't listed for plants purchased through the mail.It is better to buy plants at a local nursery or garden center when you live in warmer areas.They are familiar with the microclimates and can recommend plants for your garden.
Step 8: You should know the planting times for your zone.
Depending on your USDA Hardiness Zone, the best time to plant trees, shrubs and plants is in the fall.The first killing frost in the fall is when deciduous trees and shrubs should be planted.Perennial plants should be planted after the last hard frost.If evergreens are planted in the fall, they can be damaged by the drying winter winds and cold temperatures.The Farmer's Almanac can be used to determine when the first and last frosts will occur in your area.In USDA Hardiness Zones 10 and above, the best time to plant trees and shrubs is in late fall, winter or early spring to give the plants a chance to get established before the heat of the summer.Perennials should be planted after the last frost.
Step 9: It is a good idea to play it safe.
When selecting trees, shrubs and Perennials, take the ever-fluctuating climate into consideration.From time to time, all areas of the United States experience unusual highs and lows.Determine your Hardiness Zone and choose plants that are rated hardy for at least one Zone higher and one zone lower to make sure the plant will survive an extreme.