Plants for Difficult Sites Dr. Susan Hamilton, Univ. of TN, [email protected]

Landscape sites can present many challenges for plants.

Soils - Poor drainage or excessive drainage due to soil type.

Sunlight - Too much or too little sun can require careful plant selection. Plants which require full-sun need at least 6 hours of sunlight per day. Plants that require shade generally cannot tolerate more than 3 hours of direct sunlight per day.

Climate - North facing landscapes present a concern for wind exposure and freeze damage. South facing landscapes present a concern for intense heat and sun exposure.

Moisture - Water can be an issue. Too much leads to root diseases while too little causes plants to be stunted leading eventually to death from drought.

Salt - Roadside salt as well as seaside conditions can kill plants through desiccation. In certain regions, irrigation water can be contaminated with salt water. Pollution is also becoming a problem which weakens plants.

Deer - Deer browsing can be a serious problem in keeping plants in the landscape.

In order to tip the balance in favor of the plant, several items must be done to enhance the plant's survival on a difficult site:

1.Choose the right plant for the site. 2.Select a plant of high quality. 3.Prepare the site and the soil. 4.Prune any broken or diseased branches or roots. 5.Water thoroughly and mulch. 6.Monitor the plant's progress.

Plants exist which tolerate extreme conditions better than others and I have compiled the following lists of plants suitable for the various conditions anyone might have to face in the landscape.

Plants Which Tolerate Clay Soils: Trees: American Hornbeam, Hedge Maple, Red Maple, Silver Maple, River Birch, Hawthorn, Ash, Locust, Golden Rain Tree, Sweetgum, Shining Sumac, Green Ash, Redbud, Overcup Oak, Sugar Hackberry, Crabapple, Possum Haw, Sawtooth Oak, London Plane Tree, Cherrybark Oak, Sweet Bay Magnolia, Loblolly Pine, Spruce, Pear, Willow, Bald Cypress, Elm. Shrubs: Barberry, Quince, Dogwood shrub types, Deutzia, Euonymus, Forsythia, Witch Hazel, Junipers, Beauty Bush, Privet, Honeysuckle, Bayberry, Pyracantha, Sumac, Rugosa Rose, Spirea, Stephanandra, Yews, Arborvitae, Viburnum. Perennials: Daylily, Physostegia, Chrysogonum, Butterfly Weed, Aster, Echinacea, Elymus, Boltonia, Blackberry-Lily, Shasta Daisy, Campanula, Verbena bonariensis, Heliopsis, Liatris, Switch Grass, Rudbeckia, Silphium, Goldenrod, Indian Grass. Annuals: Sunflower, Marigold, Gomphrena, Abelmoschus, Cosmos, Amaranthus. Ground Covers: Houttuynia, Equisetum, Lysimachia, Acorus, Sedges.

Plants Which Tolerate Moist Soils: Trees: Sycamore, American Hornbeam, Possum Haw, Overcup Oak, Sugar Hackberry, Cherrybark Oak, Sweetbay Magnolia, ‘Winter King’ Hawthorn, Laurel Oak, Nutall Oak, Freeman Maple, Red Maple, Black Alder, River Birch, American Ash, Green Ash, Sweetgum, Osage Orange, Tupelo, London Planetree, Swamp White Oak, Bur Oak, Pin Oak, Willow Oak, Black Locust, Bald Cypress, Red Maple, Sugar Maple, Serviceberry, Larch, Poplar, Willow, Bald Cypress. Shrubs: Photinia, Red and Yellow-twig dogwoods, Deutzia, Forsythia, Filbert, Inkberry holly, Virginia Sweetspire, Clethra, Mountain Laurel, Calycanthus, Leucothoe, Privet, Bayberry, Wax Myrtle, Rosebay Rhododendron, Arborvitae, Viburnum. Perennials: Aegopodium, Aruncus, Asclepias, Chelone, Cimicifuga, Euparotium, Filipendula, Helenium, Helianthus simulans, Japanese Iris, Yellow Flag Iris, Sarracenia, Hibiscus, Ligularia, Lobelia, Monarda, Ranunculus, Ruellia, Tradescantia, Trollius, Valeriana, Acorus, Feather Reed Grass, Blood Grass, Miscanthus, Fountain Grass, Ribbon Grass, Northern Sea Oats, Rush. Annuals: Canna, Melampodium, Impatiens, Coleus. Vines: Swamp Rose, Cross Vine, Swamp Jessamine. Ground Covers: Chrysogonum, Lamium, Carex, Houttuynia, Equisetum, Lysimachia, Acorus.

Plants Which Tolerate Dry Soils: Trees: Japanese Black Pine, Shining Sumac, Lacebark Elm, Bald Cypress, Sugar Hackberry, Redbud, Sawtooth Oak, Eastern Red Cedar, Live Oak, Leyland Cypress, Thornless Honey Locust, Longleaf Pine, Vitex, Hedge Maple, Silver Maple, Birch, Filbert, Hawthorn, Ash, Goldenraintree, White Pine. Shrubs: Cherry Laurel, Barberry, Butterfly Bush, Quince, Smoketree, Scotch Broom, Lydia Broom, Eleagnus, Spirea, Althea, Forsythia, Nandina, Sumac, Glossy Abelia, Chokeberry, Heather, Juniper, Kerria, Beauty Berry, Chinese Holly, Yaupon Holly, Aucuba, Pyracantha, Cotoneaster, Pomegranate, Butcher’s Broom, Privet, Bayberry, Mock Orange, Potentilla, Rugosa Rose, Viburnum, Yucca. Perennials: Achillea, Aegopodium, Anthemis, Armeria, Artemisia, Asclepias, Baptisia, Bergenia, Boltonia, Centaurea, Cerastium, Ceratostigma, Coreopsis, Dianthus, Echinacea, Echinops, Eryngium, Euphorbia, Foeniculum, Gaillardia, Gaura, Geranium, Hypericum, Lamium, Lavender, Linaria, Liriope, Lychnis, Kniphofia, Malva, Kosteletskya, Penstemon, Perovskia, Rosemary, Ruta, Salvia, Santolina, Solidago, Stachys, Stokesia, Thermopsis, Thymus, Verbascum. Annuals: Vinca, Melampodium, Marigold, Wax Begonia, Lantana, Portulaca, Groundcover Petunia, Scaevola, Sweet Potato Vine, Purslane, Sunflower, Calliopsis, Cosmos, Zinnia elegans, Zinnia angustifolia.Vines: Honeysuckle, Carolina Yellow Jessamine, Porcelain Ampelopsis, Silver Lace Vine, American Bittersweet. Ground Covers: Creeping Junipers, Shore Junipers, Dwarf Junipers, Creeping Sedums, Creeping Thymes, Oenothera, Lamiastrum, Weeping Love Grass, Ribbon Grass, Daylilies, Periwinkle, English Ivy, Hypericum, Ajuga, Dianthus, Creeping Sedums, Stachys.

Plants Which Tolerate Exposed Sites: Trees: Red Maple, Serviceberry, Birch, Hornbeam, Hawthorn, Beech, Ginkgo, Locust, Scotch Pine, Austrian Pine, Quaking Aspen, Oak, Willow, Mountain Ash, Linden. Shrubs: Bearberry, Barberry, Heather, Carolina Allspice, Yellow and Red Twig dogwoods, Smoke Tree, Cotoneaster, Euonymus, P.G. Hydrangea, Juniper, Mountain Laurel, Mock Orange, Spirea, Yew, Arborvitae, Viburnum. Perennials: Rudbeckia, Sedum, Miscanthus, Candytuft, Daylily, Iris, Dianthus, Achillea, Ajuga, Kniphofia. Ground Covers: Creeping Junipers, Shore Junipers, Dwarf Junipers, Creeping Sedums, Hypericum, Weeping Love Grass, Daylilies, Periwinkle, English Ivy.

Plants Which Tolerate Urban Conditions: Trees: Freeman Maple, Norway Maple, Sycamore Maple, Red Maple, Red Horsechestnut, Black Alder, Heritage River Birch, European Hornbeam, Hackberry, Katsura Tree, Yellowwood, Turkish Filbert, White Ash, European Ash, Green Ash, Gingko, Thornless Honeylocust, Kentucky Coffeetree, Goldenraintree, Sweetgum, Tulip Tree, Osage Orange, Dawn Redwood, Tupelo, American Hophornbeam, Amur Corktree, London Plane, Sargent Cherry, Callery Pear, Sawtooth Oak, Swamp White Oak, Shingle Oak, Bur Oak, Chinkapin Oak, Pin Oak, Willow Oak, English Oak, Northern Red Oak, Shumard Oak, Live Oak, Blacklocust, Korean Mountain Ash, Scholar Tree, Baldcypress, Basswood, Littleleaf Linden, Crimean Linden, Silver Linden, Elm Hybrids, Chinese Elm, Japanese Zelkova, Lacebark Elm, Crape Myrtle, Sugar Hackberry, Chinese Pistache, Yaupon, Hawthorn, Fringetree. Shrubs: Barberry, Butterfly Bush, Quince, Summersweet, Corneliancherry Dogwood. Euonymus, Forsythia, Hibiscus, Hydrangea, Hypericum, Japanese Holly, Blue Holly, Leucothoe, Privet, Honeysuckle, Star Magnolia, Oregon Holly Grape, Bayberry, Potentilla, Pyracantha, Rugosa Rose, Willow, Spirea, Lilac, Yew, Viburnum, Wisteria, Yucca. Perennials: Sedum, Hen-and-Chicks, Dianthus, Candytuft, Ajuga, Thymes, Lysimachia, Mazus, Pennisetum, Kniphofia, Achillea, Armeria, Aurinia, Soapwort, Delsoperma, Rudbeckia, Helianthus simulans, Artemisia, Asclepias, Baptisia, Boltonia, Coreopsis, Echinacea, Eupatorium, Gaura, Candytuft, Goldenrod, Stoke’s Aster, Verbena canadensis, Ruellia. Annuals: Periwinkle, Castor Bean, Purslane, Scaevola, Abelmoschus, Cosmos, Cleome, Cuphea, Gomphrena, Portulaca, Rudbeckia, Nierembergia, Verbena, Lantana, Groundcover Petunia, Portulaca, Scaevola, Sweet Potato Vine, Tithonia, Zinnia angustifolia, Amaranthus, Pentas. Ground Covers: Mondo Grass, Thymes, Candytuft, Sweet Woodruff, Roman Chamomile, Woolly Yarrow, Creeping Speedwell, Hypericum, English Ivy, Periwinkle, Pachysandra, Stachys.

Plants Which Tolerate Deep Shade: Trees: Hedge Maple, Serviceberry, Redbud, Fringetree, Flowering Dogwood, Magnolia. Shrubs: Bearberry, Barberry, Boxwood, Carolina Allspice, Sweetshrub, Sweetfern, Euonymus, Fatshedera, Aucuba, Kalmia, Filbert, Hydrangea, Virginia Sweetspire, Mountain Laurel, Leucothoe, Privet, Pieris, Honeysuckle, Oregon Holly Grape, Nandina, Siberian Cypress, Honeysuckle, Pieris, Pyracantha, Rhododendron, Yew, Arborvitae, Hemlock, Viburnum, Serviceberry, Witch Hazel. Perennials: Carex, Bleeding Heart, Lobelia, Japanese Anemone, Sweet Woodruff, Turtlehead, Acanthus, Alchemilla, Lily-of-the-Valley, Agapanthus, Jacobinia, Heuchera, Toadlily, Lamiastrum, Phlox divaricata, Tradescantia, Hosta, Lenten Rose, Black Snakeroot, Astilbe, Pulmonaria, Tiarella, False Solomon’s-Seal, Chrysogonum, Celandine Poppy, Epimediums, Wild Ginger. Annuals: Impatiens, Begonia, Torenia, Browallia, Caladium, Lobelia, Coleus. Ground Covers: Black Mondo Grass, Japanese Painted Fern, Lamiastrum, Sweet Woodruff, Lily-of-the-Valley, Pachysandra, Tiarella, Wild Ginger, Crested Iris, Chrysogonum, Bishop’s Weed, English Ivy, Periwinkle, Hosta, Ajuga, Strawberry Begonia.

Plants Tolerant of Dry Shade: Shrubs: Berberis wilsoniae, Buxus sempervirens, Cotoneaster ‘Cornubia’, Danae, Euonymus, Lonicera pileata, Mahonia, Rubus tricolor, Butcher’s Broom, Skimmia. Perennials: Bear’s Breeches, Lady’s Mantle, Euphorbia robbiae, Iris foetidissima, Lamiastrum, Lamium, Liriope, English Ivy, Periwinkle, Carex pendula, Dryopteris filix-mas, Epimedium, Polystichum setiferum, Trachystemon orientale.

Plants Resistant to Deer: Trees: Maple, Birch, Hornbeam, Redbud, Dogwood, Ash, Hawthorn, Beech, Ginkgo, Larch, Sweetgum, Tulip Tree, Magnolia, Tupelo, Spruce, Sycamore, Oak, Willow, Bald Cypress, Linden, Elm, Japanese Zelkova. Shrubs: Barberry, Boxwood, Blue Mist Spirea, Buddleia, Quince, Sweetshrub, Cotoneaster. Perennials: Achillea, Alchemilla, Allium, Amsonia, Angelica, Aquilegia, Artemisia, Aruncus, Asclepias, Aster, Astilbe, Aurinia, Baptisia, Bergenia, Boltonia, Calamint, Crocosmia, Dianthus, Echinacea, Eryngium, Eupatorium, Filipendula, Geranium, Geum, Heuchera, Iberis, Iris, Lamium, Lavandula, Linaria, Monarda, Nepeta, Oenothera, Origanum, Penstemon, Perovskia, Phalaris, Rosemary, Rudbeckia, Salvia, Sedum, Goldenrod, Tanacetum, Thymus, Verbascum, Veronica. Annuals: Ageratum, Alyssum, Melampodium, Morning Glory, Annual Periwinkle, Parsley, California Poppy, Pentas, Cleome, Plectranthus, Coreopsis, Poppy, Cornflower, Salvia, Dusty Miller, Snapdragon, Nicotiana, Verbena, Gaillardia, Wax Begonia, Lobelia, Zinnia, Marigold, Brugmansia, Scutellaria, Potato Vine, Sunflower, Castor Bean, Ruellia, Lantana, Four O’clocks. Ground Covers: Ajuga, Dianthus, Creeping Sedums, Stachys, Vinca, Carolina Jessamine, Trumpetvine, Cherokee Rose, Wisteria, Honeysuckle.

Plants Which Tolerate Salt: Trees: Japanese Black Pine, Eastern Red Cedar, Southern Magnolia, Live Oak, Yaupon, Russian Olive, Trident Maple, Hedge Maple, Sycamore Maple, Norway Maple, Black Alder, Hawthorn, Green Ash, Ginkgo, Honeylocust, Goldenraintree, Osage Orange, London Planetree, Sargent Cherry, Callery Pear, English Oak, Northern Red Oak, Black Locust, Scholar Tree, Baldcypress. Shrubs: Saltshrub, Yaupon Holly, Elaeagnus, Butcher’s-broom, Bayberry, Scotch Broom, Pittosporum, Yucca, Agave, Viburnum suspensum, Viburnum tinus, Indian Hawthron, Bottlebrush. Perennials: Gaillardia, Achillea filipendulian, Artemisia, Chrysanthemum Pacificum, Kniphofia, Crinum, Daylily, Society Garlic. Annuals: Ageratum, Portulaca, Verbena, Cuphea, Dusty-miller, Lantana, Sweet Alyssum, Geranium, Ivy Geranium, Calendula, Gazania, Purslane, Wax Begonia, Ornamental Cabbage. Vines: Trumpet Creeper, Carolina Yellow Jessamine, Virginia Creeper. Groundcovers: English Ivy, Partridgeberry, Virginia Creeper, Shore Juniper, Creeping Juniper, Cordgrass, Carolina Yellow Jessamine, Euonymus Wintercreeper.

Tenacious Plants for Sunny Banks and Slopes: Forsythia, Glossy Abelia, Weigela, Eleagnus, PG Hydrangea, Loropetalum, Willowleaf Cotoneaster, Spreading Euonymous, Clusterberry Contoneaster, Primrose Jasmine, Shore Juniper, Creeping Juniper, Parson’s Juniper, Leucothoe, Dwarf Abelias, Warminster Broom, Rockspray Contoneaster, Showy Jasmine, Weeping Love Grass, Hypericum, Memorial Rose, Daylilies, Liriope, Crown Vetch, Viburnums.