The best plants to grow in Virginia include any and all plants that are native to the area. More and more, nurseries across the country are propogating and promoting native plants, which can be used by professional and amateur landscapers alike.
Native species promote local ecologies. Wild-collected plants--that is, plants that are not native to Virginia but that can be cultivated to grow in Virginia--threaten the population size and genetic diversity of native plants.
Native species are perfectly suited for Virginia's conditions. Unlike wild-collected plants, which must be cultivated to survive Virginia's climate, native species are acclimated to the soil and moisture conditions, sunlight exposure, and overall environment, a fact that will increase your likelihood of success.
Alien species are not necessarily harmful--in fact, they can be beneficial to the environment and your landscape--but a landscape designed with native plant species is often more beautiful because the native plants don't just grow in Virginia, they thrive.
Virginia is divided into three regions: the coastal plain, the piedmont, and the mountains. Determine in which region you live so that you can plant the proper species in your landscape or garden.
The coastal plain of Virginia ranges from the Atlantic Ocean in the east to the fall line in the west. There are a variety of plant species that are native to this specific region, including the redbay (Persea borbonia), the highbush blueberry (Vaccinium corymbosum), and tulip tree (Liriodendron tulipfera).
From the fall line in the east to the edge of the Blue Ridge mountains in the west constitues the piedmont. Plants that are native to the piedmont include the Catawba rhododendron (Rhododendron catawbiense), the willow oak (Quercus phellos), and the red chokeberry (Aronia arbutifolia).
The mountains, of course, constitute the mountain region of the state. Native mountainous plants include the New England aster (Aster novae-engliae), the wood lily (Lilium philadelphicum), and the flame azalea (Rhododendron calendulaceum).
Many plant species are native to the state as a whole, and may be planted throughout Virginia if the environment is correct. The mountain laurel (Kalmia latifolia), spicebush (Lindera benzoin), and the pinxter flower (Rhododendron periclymenoides) are all shrubs that are native to all regions of Virginia. If you're looking for trees that are native to the state, look no further than the downy serviceberry (Amelanchier arborea), the paw paw (Asimina triloba), the American holly (Ilex opaca), and the red mulberry (Morus rubra).
One of the most important considerations you should have when landscaping or planting is what alien plants are invasive. Invasive plants choke native plants, an act that has a negative impact on the ecology of the state. Planting alien species isn't a problem as long as the plants are not listed as invasive. Invasive trees include the Norway maple (Acer platanoides), the Chinaberry (Melia azedarach), the white poplar (Populus alba), and the Siberian elm (Ulmus pulmia). Invasive shrubs include the Japanese barberry (Berberis thunbergii), the Autumn olive (Elaeagnus umbellata), the border privet (Lingustrum obtusifolium), and the memorial rose (Rosa wichuraiana).
For a complete list of invasive species, consult the Virginia Native Plant Society's website.