Planting Zone Chart

The following chart is USDA zones for planting:

This map supersedes U.S. Department of Agriculture Miscellaneous Publication 814, "Plant Hardiness Zone Map," which was revised in 1965.  This 1990 version shows in detail the lowest temperatures that can be expected each year in the United States, Canada, and Mexico.  These temperatures are referred to as "average annual minimum temperatures" and are based on the lowest temperatures recorded for each of the years 1974 to 1986 in the United States and Canada and 1971 to 1984 in Mexico.  The map shows 10 different zones, each of which represents an area of winter hardiness for the plants of agriculture and our natural landscape.  It also introduces zone 11 to represent areas that have average annual minimum temperatures above 40 F (4.4 C) and that are therefore essentially frost free.

How to Use the New Map 
Zones 2-10 in the map have been subdivided into light- and dark-colored sections (a and b) that represent 5 F (2.8 C) differences within the 10 F (5.6 C) zone.  The light color of each zone represents the colder section; the dark color, the warmer section.  Zone 11 represents any area where the average annual minimum temperature is above 40 F (4.4 C). The map shows 20 latitude and longitude lines.  Areas above an arbitrary elevation are traditionally considered unsuitable for plant cropping and do not bear appropriate zone designations.  There are also island zones that, because of elevation differences, are warmer or cooler than the surrounding areas and are given a different zone designation.  Note that many large urban areas carry a warmer zone designation than the surrounding countryside.  The map-contains as much detail as possible, considering the vast amount of data on which it is based and its size.

Zone 1 

Below -45.6 C
Below -50 F

Betula glandulosa  (Dwarf birch)
Empetrum nigrum  (Crowberry)
Populus fremuloides  (Quaking aspen)
Potentilla pensylvanica  (Pennsylvania cinquefoil)
Rhododendron lapponicum  (Lapland rhododendron)
Salix reticulate  (Netleaf willow)

Zone 2
-50 to -40 F
-45.6 to -40 C

Betula papyrifera  (Paper birch)
Cornus canadensis  (Bunchberry dogwood)
Elaeagnus commutata  (Silverberry)
Larix laricina  (Eastern larch)
Potentilla fruticosa  (Bush cinquefoil)
Viburnum trilobum  (American cranberry bush)

Zone 3
-40 to -30 F
-40 to -34.5 C

Berberis thunbetgii  (Japanese bayberry)
Elaeagnus angustifolia  (Russian olive)
Junipercus communes  (Common juniper)
Lonicera tatarica  (Tatarian honeysuckle)
Malus baocata  (Siberian crabapple)
Thuia occidentalis (American arborvitae)

Zone 4
-30 to -20 F
-34.5 to -28.9 C

Acer saccharum  (Sugar maple)
Hydrangea paniculata  (Panicle hydrangea)
Juniperus chinensis  (Chinese juniper)
Ligustrum amurense  (Amur River privet)
Parthenocissus quinquefolia  (Virginia creeper)
Spiraea x vanhouttei  (Vanhouffe spirea)

Zone 5
-20 to -10 F
-28.9 to -23.3 C

Cornus florida  (Flowering dogwood)
Deutzia gracilis  (Slender deutzia)
Ligustrum vulgare  (Common privet)
Paithenocissus tricuspidata  (Boston ivy)
Rosa multiflora  (Japanese rose)
Taxus cuspidata  (Japanese yew)

Zone 6
-10 to 0 F
-23.3 to -17.8 C

Acer palmatum  (Japanese maple)
Buxus sempervirens  (Common boxwood)
Euonymus follunei  (Winter creeper)
Hedera helix  (English ivy)
Ilex opaca  (American holly)
Ligustrum ovalifolium  (California privet)

Zone 7
0 to 10 F
-17.8 to -12.3 C

Acer macrophylium  (Bigleaf maple)
Rhododendron Kurume hybrids   (Kurume azalea)
Cedrus atlantica  (Atlas cedar)
Cotoneaster microphylla  (Small-leaf cotoneaster)
Ilex aquifolium  (English holly)
Taxus baccata  (English yew)

Zone 8
10 to 20 F
-12.3 to -6.6 C
Arbutus unedo  (Strawberry tree)
Choisya temata  (Mexican orange)
Olearia haastii  (New Zealand daisy-bush)
Pittosporum tobira  (Japanese pittosporum)
Prunus laurocerasus  (Cherry-laurel)
Viburnum tinus  (Laurestinus)

Zone 9
20 to 30 F
-6.6 to -1.1 C

Asparagus setacous  (Asparagus fern)
Eucalyptus globulus  (Tasmanian blue gum)
Syzygium paniculatum  (Australian bush cherry)
Fuchsia hybrids  (Fuchsia)
Grevillea robusta  (Silk-oak)
Schinus molle  (California pepper tree)

Zone 10
30 to 40 F
-1.1 to 4.4 C

Bougainvillea spectabilis  (Bougainvillea)
Cassia fistula  (Golden shower)
Eucalyptus citriodora  (Lemon eucalyptus)
Ficus elastica  (Rubber plant)
Ensete ventricosum  (Ensete) 
Roystonea regia   (Royal palm)

Stress Factors- We became aware of additional stresses to plants during the 1970's.  Acid rain, gaseous and particulate pollution, security lighting, and toxic wastes, among many other stress factors, have significantly increased the potential for unsatisfactory performance of landscape plants.  We need to document the tolerances of plants to these factors.

New Plant Management Systems- New techniques of planting, transplanting, watering, fertilizing, and providing pest control measures have done much to increase the vigor of landscape plants.  But used unwisely, these same measures can reduce plant hardiness.

Artificial Environments- We have pushed the use of plants into totally artificial environments such as expressways, malls, elevated decks, and buildings where plant roots are totally removed from the ground and its warming influence.  The assortment of plants that can adapt to such environments is proving to be very restricted.  Hardiness ratings alone are inadequate to guide landscapers in selecting the most successful plants.

The ability to predict whether a newly collected species or cultivar can be successfully grown in a location is fundamental to the continued productivity of America's agriculture and to the survival of our landscapes.  The plants in our urban spaces, farms, fields, and forests consist of native vegetation and exotic plants introduced into our land from all over the world.

All plants must be placed in an environment that meets their basic requirements: 

Day length- Day length is usually the most critical factor in regulating vegetative growth, flower initiation and development, and the induction of dormancy.  Plants survive only when the day length promotes their growth and prepares them for the seasonal changes.

Radiation- Most plants respond to radiation in the 270- to 3000-nm region.  Cloudy, rainy days coupled with the shade provided by nearby plants and structures can significantly reduce the amount of radiation available.  Plants survive only where the amount is within a specified range.

Temperature- Plants grow best within an optimum range of temperatures; and the range may be wide for some species, narrow for others.  Plants survive only where temperatures allow them to metabolize.

Frost- Plants differ in ability to survive frost, their responses varying from immediate death to sustained performance.  The previous