Planters for Permanence
A relatively new feature in gardens is the planter. Contemporary houses are frequently designed with built-in planters, and traditional types have them at entranceways, on terraces, and beside garages. On the West Coast especially, many houses and gardens include planters of such durable materials as concrete, brick, or blue stone. There are two types-the permanent planter attached to the house and the movable one bought or built to suit a particular need. Some gardeners maintain several for replacement as plants pass their prime. Planters are rectangular, square, oblong, triangular, hexagonal, circular, or free form. Like pots and tubs, their value is largely architectural.
Permanent
Stationary planters outdoors must be planned with care. Those attached to entranceways or the front of a house should be designed in proper scale and proportion, and with good drainage facilities at the start, for unlike the portable type, they cannot be moved or easily replaced. It is important not to place them over ledges or other obstructions through which water cannot easily pass. Usually these planters are open to the ground. If the soil is clayey, some should be removed and replaced with a layer of stones or cinders to insure drainage.
Movable
Mobile planters can be carried, pushed, or wheeled to various positions. Desirable construction materials include wood-with redwood, cedar and cypress heading the list-metals, fiberglass, plastic and various synthetic products. Whatever you buy, make yourself or have made, be certain beforehand that you know what the material looks like, how it behaves under your weather conditions and how durable it is. A greater investment in the beginning will pay off in the end.
Choosing the Plants
When selecting the plant material, give thought to scale. In large planters, trees and shrubs, including needle and broad-leaved evergreens, should be grown. With annuals, rely on tall kinds, like cosmos, African marigolds and cleome. If planters are long, repeat one of the plants for unity and harmony. Usually some trailing plants are needed along the edge to soften it.
The permanent planter requires trees and shrubs for year-round effect. Except in the very large planters attached to big buildings, rely on small or dwarf types. Among trees for colder climates, consider Japanese maple and its varieties, ornamental magnolias, flowering cherries, including the weeping forms, Tatarian maple, flowering dogwood, birches, dwarf forms of Scotch, red, and Japanese black pines, upright arborvitaes and junipers and fastigiate trees, as the upright European hornbeam or linden. The flowering crabs are superb, especially the white-flowering Sargent, which remains low and spreading.
Among evergreen and deciduous shrubs, there are the Japanese yews, spreading and ground-cover types of junipers, dwarf arborvitae, shrubby evergreen euonymus, skimmia, cherry laurel, mahonias, leucothoe, dwarf Hin-oki cypress, the convex-leaved and other hollies, camellias, azaleas, slender deutzia, dwarf rhododendrons, fothergilla, flowering quinces, heathers, and the mugo pine. Good barberries include the Wintergreen (Berberis julianae), Korean (B. koreana), Mentor (B. mentorensis), three-spine (B. triacanthophora), and warty (B. verruculosa). The dwarf forms of the Japanese barberry, including Crimson Pygmy and the low Berberis thunbergi minor, are superior plants.
Cotoneasters are valuable because they stay small, have attractive foliage and red berries, develop a loose, informal habit, grow in a variety of situations and withstand wind. Certainly worth considering are the bearberry (Coton-easter dammeri), rock spray (C. horzontalis), the small-leaved cotoneaster (C. microphylla), and the delightful prostrate form, Cotoneaster adpressa.
Several specimens of trees or shrubs make a pleasing combination with one type of ground cover or trailer, like dwarf Japanese yew with English ivy, Korean boxwood with myrtle, or dwarf Hinoki cypress with pachysandra. Other good ground covers to combine with evergreens include pachistima, prostrate junipers, bearberry or arcto-staphyllos, yellowroot, sweet fern, trailing euonymus, as the purple-leaf type {Euonymus fortunei coloratus), leio-phyllum or sand myrtle, ajuga, and various thymes and sedums.
Flowers for Color
Planters also need flowers for color. You can start with spring bulbs, like daffodils and tulips, continue with annuals, and finish the season with chrysanthemums. For a pleasing edging, there is the permanent English ivy. Except for small planters, flowering plants are best combined with shrubs. For planters that are three feet or longer, petunias and geraniums, though colorful, are not tall enough.
Built-in types look well with tropical foliage and flowering plants, which are summer subjects in the North. In sun, for example, the bold leaves of rubber plants (include a few of the variegateds), small palms, Japanese aralia, large-leaved philodendrons, scherfleras, alligator pears and pandanus look well together. Smaller kinds- crotons in variety, hibiscus, grevillea, brunfelsia, and flowering maples-offer spots of color.
Cannas, with huge, bold leaves, have a modern look. Hybrid angel's trumpets, with large leaves and dramatic white flowers, are dynamic. In smaller planters, dwarf varieties of cannas-Pfitzer's Cherry-Red, Pfkzer's Primrose Yellow, and Pfitzer's Shell Pink-are more desirable. Castor bean, difficult to place because of its enormous leaves, is excellent for the large planters of contemporary houses, as is elephant's ear, started easily from tubers.
These for Shade
In partial shade or filtered sunlight, the variety can be even greater. Start with the clean-cut modernistic lines of large-leaved philodendrons-Philodendron dubia, P. has-tatum, or P. jaciniatum. Many other philodendrons are suitable. Tall and medium kinds give height, and the trailing, heart-leaved philodendron, will fall gracefully over the edge of a planter.
The long list of suitable tropicals includes dracaenas, dieffenbachias, Chinese rubber plants, foliage begonias like the rex types, aglaonemas, anthuriums, aphelandra, ardisia, aucuba, bromeliads, cissus, crotons, ficus, ferns, peperomias, pothos, nephthytis, spathiphyllum, syngonium, and tradescantias. Consider also the fancy leaves of alocasias, many with bizarre patterns. In planters, you can group the tropical foliage plants you grow indoors in winter by inserting the pots in damp peatmoss or Vermiculite.
For Warm Regions
In warm areas, with little or no freezing, tropical plants can be grown outdoors all year round. Delightful in Florida are crotons, and there are so many varieties, with odd leaf forms and colors, some that even look like different plants. Easy to grow, they withstand neglect and pruning. Camellias, tender hollies, Chinese hibiscus, gardenias, poinsettias, pittosporum, clivias, agapanthus, bamboos, podocarpus, loquat, citrus, tender azaleas, sansevieria, cymbidium and other orchids, fancy-leaved caladiums, bird of paradise, epiphyllums-all have exciting possibilities for planters in the South.