The idea of an outdoor living space that's elevated, whether a mere three or four feet off the ground or at second-story level, has irresistible appeal. And the appeal isn't only for families looking to extend their indoor living space. A deck presents the chance for a gardener to invent a new way of living in the garden. What gardener hasn't thought of having a viewing platform-a place to get a bird's-eye view over the garden, a real panorama instead of the typical narrow glimpse afforded by an upstairs window?
We may have memories of looking out from the tower at Sissinghurst, we may dream of finding a house with a really big rock outcropping, we may even consider getting into serious grading. But the solution can be much more simple. All we really need is a house with a high deck. And if it has a low deck? Those offer opportunities for gardeners, too.
HIGH DECKS
A high deck, one at least 10 feet off the ground, can be an adult interpretation of your childhood tree house if you design a private "forest" around it.
Ask the basic questions: do you need to screen a view or frame one? Do you want the feel of an evergreen or a deciduous forest? Will this be a place to watch birds? (If so, you'll want to choose trees that serve as nesting sites or food sources and add birdhouses, a feeding table, and a birdbath.)
But your first step is to create the sense of leafy tree house privacy. Your initial budget should go to planting a grove of fast-growing small trees along at least two sides of the deck. A grouping of three to seven two-inch caliper saplings in mixed heights will give the sense of a young forest grove. Desirable features include a narrow vaselike structure, early leaf break, good fall color, and a bonus of interesting bark, fragrance, or flowers. Avoid species that are vulnerable to ice and wind damage, and look for trees that establish readily in your area, need little pruning, and suit the architectural style of your house.
You might choose aspens or birches, perhaps Betula utilis var. jacquemontii for its pale creamy bark or B. nigra 'Heritage' for its fast growth, upright habit, and early leaf out, which will veil your tree house in a haze of spring green.
For a more formal effect, consider the light shade given by a group of honeylocusts (Gleditsia triacanthos).
If you live in an older home, think of creating the sense of an orchard with pears or crab apples or serviceberries, like Amelanchier xgrandiflora 'Princess Diana', with its gray bark, early spring bloom, and red fruit that is eagerly sought by many birds.
Imagine looking down on the flowers of kousa dogwood (Cornus kousa), the way you've always wanted to see them.
All of these trees invite the establishment of understory plants, the fragrant, colorful shrubs that you will weave among their trunks, hiding the base of the deck and creating a separate room-a hidden woodland alcove below the deck.
LOW DECKS
Suppose your deck is just a few feet off the ground. Because they are low, these decks all too often turn into a kind of extended mud room or, at best, an outdoor potting station. But they can be reinvented as clearings in a prairie or tropical rafts floating in a summer sea of grasses and flowers. Keep the sense of wide-open skies with low shrubs and grasses that give partial privacy when you're sitting down, but let you view the rest of the garden when you stand up.
Surround your summer clearing with fragrant easy-care shrubs, such as dwarf Korean lilac (Syringa meyeri 'Palibin') and smooth hydrangea (Hydrangea arborescens), switch grass (Panicum virgatum 'Prairie Skies'), and groups of joe-pye weed (Eupatorium purpureum), queen of the prairie (Filipendula rubra), and coneflowers (Echinacea). Then dress the deck with rustic-looking containers-galvanized buckets, milk pails, and whiskey barrels-full of traditional favorites, such as pelargoniums, zinnias, or petunias. Set up the barbecue, pull out the canvas deck chairs, and prepare the lemonade.
A low deck is also an ideal setting for fantasy gardening. Create a tropical scene with all-weather rattan, colorful umbrellas, and candle lanterns. Add a chiminea, a barbecue, and lots of glazed pots. Large glossy leaves, variegated foliage, and the sound of bamboo and grasses rustling in the breeze make this deck a port of call on a tropical cruise.
Choose a tree with inherent drama, perhaps a big-leaved magnolia (Magnolia macrophylla or M. tripetala), to draw your eye just out from the house. Close to the deck, group red-leaved shrubs, such as Weigela florida Wine and Roses, purple smoke bush (Cotinus coggygria 'Velvet Cloak'), purple filbert (Corylus avellena 'Red Majestic'), or black elder (Sambucus nigra 'Black Lace'). Enhance this frame by mixing in clumps of tall ornamental grasses.
Add some hibiscus-the woody rose of Sharon (Hibiscus syriacus) or the hardy, herbaceous H. moschuetos-and enrich the scene with cannas (Canna), bananas (Musa), elephant's ears (Alocasia or Colocasia), pineapple lilies (Eucomis ), and ginger lilies (Hedychium).
All you need now is a mai tai and some music, and you're in the tropics.
Kousa dogwood photo by Hans J E /CC BY-SA 2.0
