Zone 1

Below -45.6 C
Below -50 F

Betula glandulosa  (dwarf birch)
Empetrum nigrum  (black crowberry)
Populus tremuloides  (quaking aspen)
Potentilla pensylvanica  (Pennsylvania cinquefoil)
Rhododendron lapponicum  (Lapland rhododendron)
Salix reticulata  (netleaf willow)

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

Betula papyrifera  (paper birch)
Cornus canadensis  (bunchberry)
Elaeagnus commutata  (silverberry)
Larix laricina  (eastern larch)
Dasiphora fruticosa  (shrubby cinquefoil)
Viburnum opulus var. americanum  (American cranberry-bush)

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

 Acer saccharum  (sugar maple)
Elaeagnus angustifolia  (Russian olive)
Hydrangea paniculata  (panicle hydrangea)
Juniperus communis  (common juniper)
Lonicera tatarica  (Tatarian honeysuckle)
Malus baccata  (Siberian crabapple)
Parthenocissus quinquefolia  (Virginia creeper)
Spiraea x vanhouttei  (Van Houtte spirea)
Thuja occidentalis (American arborvitae)

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

Berberis thunbergii  (Japanese barberry)
Juniperus chinensis  (Chinese juniper)
Ligustrum obtusifolium subsp. suave  (Amur privet)
Ligustrum vulgare  (common privet)
Parthenocissus tricuspidata  (Boston ivy)
Taxus cuspidata  (Japanese yew)

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

 Acer palmatum  (Japanese maple)
Cornus florida  (flowering dogwood)
Cotoneaster microphyllus  (small-leaf cotoneaster)
Deutzia gracilis  (slender deutzia)
Euonymus fortunei  (winter-creeper)
Rosa multiflora  (multiflora rose)

Zone 6
-10 to 0 F
-23.3 to -17.8 C
Buxus sempervirens  (common boxwood)
Cedrus atlantica  (Atlas cedar)
Hedera helix  (English ivy)
Ilex opaca  (American holly)
Ligustrum ovalifolium  (California privet)
Prunus laurocerasus  (cherry-laurel)
Taxus baccata  (English yew)

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

Acer macrophyllum  (bigleaf maple)
Rhododendron Kurume Group  (Kurume azalea)
Ilex aquifolium  (English holly)

Zone 8
10 to 20 F
-12.3 to -6.6 C
Arbutus unedo  (strawberry-tree)
Choisya ternata  (Mexican orange)
Olearia x haastii  (New Zealand daisy-bush)
Pittosporum tobira  (Japanese pittosporum)
Viburnum tinus  (laurustinus)

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

Asparagus setaceus  (asparagus-fern)
Eucalyptus globulus  (Tasmanian blue gum)
Fuchsia hybrids  (fuchsia)
Grevillea robusta  (silky-oak)
Schinus molle  (California pepper-tree)
Syzygium paniculatum  (Australian brush-cherry)

Zone 10
30 to 40 F
-1.1 to 4.4 C

Bougainvillea spectabilis  (bougainvillea)
Cassia fistula  (golden shower)
Corymbia citriodora  (lemon-scented gum)
Ficus elastica  (rubber plant)
Ensete ventricosum  (Abyssinian-banana)
Roystonea regia  (royal palm)

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