Region defined by minimum temperature relevant to the plant survival
A hardiness zone is a geographic area defined as having a certain average annual minimum temperature, a factor relevant to the survival of many plants. In some systems other statistics are included in the calculations. The original and most widely used system, developed by the United States Department of Agriculture (USDA) as a rough guide for landscaping and gardening, defines 13 zones by long-term average annual extreme minimum temperatures. It has been adapted by and to other countries (such as Canada) in various forms. A plant may be described as "hardy to zone 10": this means that the plant can withstand a minimum temperature of 30 to 40 °F (−1.1 to 4.4 °C).
Unless otherwise specified, in American contexts "hardiness zone" or simply "zone" usually refers to the USDA scale. However, some confusion can exist in discussing buildings and HVAC, where "climate zone" can refer to the International Energy Conservation Code zones, where Zone 1 is warm and Zone 8 is cold.
Other hardiness rating schemes have been developed as well, such as the UK Royal Horticultural Society and US Sunset Western Garden Book systems. A heat zone (see below) is instead defined by annual high temperatures; the American Horticultural Society (AHS) heat zones use the average number of days per year when the temperature exceeds 30 °C (86 °F).
A hardinesszone is a geographic area defined as having a certain average annual minimum temperature, a factor relevant to the survival of many plants...
(plants), the ability of plants to survive adverse growing conditions Hardinesszone, area in which a category of plants is capable of growing, as defined...
Zone 2 may refer to: Travelcard Zone 2, of the Transport for London zonal system Hardinesszone, a geographically defined zone in which a specific category...
Zone 3 may refer to: Travelcard Zone 3, of the Transport for London zonal system Hardinesszone 3, a geographically defined zone in which a specific category...
disturbances. Examples of empiric classifications include climate zones defined by plant hardiness, evapotranspiration, or associations with certain biomes, as...
Zone 5 may refer to: Travelcard Zone 5, of the Transport for London zonal system Hardinesszone, a geographically defined zone in which a specific category...
Climate classification Clime Hardinesszone Polar regions of Earth Subtropics Temperate climate Tropics "The Five Geographical Zones Of The World". WorldAtlas...
lacking control over nature e.g. 'the wild Amazonian rainforests'. Hardinesszone Tropical ecology Tropical marine climate Tropical year "How much land...
life for an extended time span Frigid zone, a geographical zone on Earth Hardinesszone, a geographically defined zone in which a specific category of plant...
passion vine) Due to the microclimate, the plant hardinesszone in the Sydney area would range: Zone 11a (4.4 to 7.2°C): Sydney CBD Sydney Harbour North...
Zone 6 may refer to: Travelcard Zone 6, of the Transport for London zonal system Hardinesszone, a geographically defined zone in which a specific category...
Zone 1 may refer to: Hardinesszone, a geographically defined zone in which a specific category of plant life is capable of growing Fare Zone 1, of the...
(See List of Caladium cultivars.) It can be planted outside in USDA HardinessZone 10 as an ornamental. It is a problematic invasive species in Trinidad...
HardinessZone 7. As the common name "hardy begonia" implies, it is winter hardy in some temperate regions. It can overwinter well in hardinesszone 9a...
Southeast Asia, from China and Japan south to Indonesia and Vietnam (USDA hardinesszone 6–11). It is a perennial plant, growing from a large corm up to 25 cm...
Zone 9 may refer to: Travelcard Zones 7-9, of the Transport for London zonal system Hardinesszone, a geographically defined zone in which a specific...
across New Hampshire. The 1990 USDA plant hardinesszones for New Hampshire range from zone 3b in the north to zone 5b in the south. Metropolitan areas in...
inches (148 mm) on 09/17/2004. During the winter months, the plant hardinesszone is 5b with an average annual extreme minimum air temperature of −13...
Zone 8 may refer to: Travelcard Zones 7-9, of the Transport for London zonal system Hardinesszone, a geographically defined zone in which a specific...
the Perennial Plant Association (PPA). Based on the (USDA) Hardinesszone it is hardy in zones 3 to 8. RHS A-Z encyclopedia of garden plants. United Kingdom:...
Zone 4 may refer to: Hardinesszone, a geographically defined zone in which a specific category of plant life is capable of growing Marcory Zone 4, one...
because it is warmed by the Gulf Stream and the Baltic Sea, and the hardinesszone of Simrishamn is 8a, comparable to Paris, France. Simrishamn is first...
Muscadine grapes. The region has a humid subtropical climate and the hardinesszone ranges from 8b in the south to 7b in some Tennessee portions of the...