What is the Mid-Atlantic?
The "Middle Atlantic" colonies of the original thirteen were considered to be New York, Pennsylvania, New Jersey and Delaware. We also include the District of Columbia, Maryland, Virginia, and West Virginia. The "Mid-Atlantic" is the area east of the Appalachian Mountains. The clearest picture of the "Mid Atlantic" can be seen in Rob Proctor's "Naturalizing with Bulbs". Zones in this region range from Zone 4 in northern New York State to Zone 8 south of Norfolk, Virginia. Plant cultivation information from the Mid-Atlantic forum may be applicable to Illinois, Indiana, Ohio, Kentucky, and Missouri.
From the US National Arboretum in Washington, DC.
Cold Hardiness Ratings for Selected Woody Plants
Representative plants are listed under the coldest zones in which they normally succeed
Zone Ratings -- Average Annual Minimum Temperature Range
Zone 4 (-30 to -20 F) (-43.5 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) Parthenocissus 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)
(Source: USDA Miscellaneous Publication No. 1475. Issued January 1990. Authored by Henry M. Cathey while Director, U.S. National Arboretum. Edited, formatted and prepared for the US National Arboretum web site by Ramon Jordan, March 1998 & Revised March 2001. U.S. National Arboretum, Agricultural Research Service, U.S. Department of Agriculture, Washington, DC 20002. Note: USDA Miscellaneous Publication No. 1475 is not copyrighted, and permission to reproduce all or any part of it is not required.)