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all about zones

Growing/Hardiness Zone FAQ

  1. What are USDA Hardiness Zones?

USDA Hardiness Zones are a way of categorizing different growing regions according to average minimum temperatures. The USDA Plant Hardiness Zone Map was created in 1960 and is divided into 13 different zones, each one representing a 10 degree Fahrenheit range. This is helpful for gardeners in figuring out what plants are best suited for their climate and which ones to avoid.

  1. How do I determine my USDA Hardiness Zone?

Determining your hardiness zone is easy. Just look up your zip code on the USDA Plant Hardiness Zone Map, which can be found online or in gardening books. Once you know your zone, you can then plan your garden accordingly.

  1. Is my hardiness zone the same as my USDA Growing Zone?

The USDA Hardiness Zone Map and the USDA Growing Zone Map are two different things. The Hardiness Zone Map is based on average low temperatures, while the Growing Zone Map is based on average annual temperatures and the length of the growing season. So, while your hardiness zone might be the same as your growing zone, they don’t necessarily have to be.

  1. What is the coldest zone?

The coldest zone is Zone 1, which is located in northern Canada. The average minimum temperature in Zone 1 is -60 to -50 degrees Fahrenheit.

  1. What is the warmest zone?

The warmest zone is Zone 13, which is located in Hawaii and other tropical locations. The average minimum temperature in Zone 13 is 50 to 60 degrees Fahrenheit.

  1. Can plants be grown in multiple zones?

Yes, many plants can be grown in multiple zones. There are some plants, such as azaleas and rhododendrons, that are best suited to certain zones, but can usually be grown in other zones with a bit of extra care.

  1. Are hardiness zones the same for all plants?

No, not all plants have the same hardiness zones. Some plants, like roses, are hardy in a wide range of zones, while other plants, like tropical plants, are only hardy in certain zones.

  1. How often is the hardiness zone map updated?

The USDA Hardiness Zone Map is updated every 10 years or so, as conditions and temperatures can fluctuate over time.

  1. Are there any other factors to consider when planting in different hardiness zones?

Yes, there are several other factors to consider when planting in different hardiness zones. The amount of sunlight, soil quality, and moisture levels are all important factors to consider when choosing plants for a particular zone.

  1. Does the hardiness zone map apply to all parts of the US?

Yes, the hardiness zone map applies to all parts of the US, including Alaska and Hawaii. The map is divided into 13 different zones, each one representing a 10 degree Fahrenheit range.