GARDENING

the laying out and care of a plot of ground devoted partially or wholly to the growing of plants such as flowers, herbs, or vegetables. Gardening can be considered both as an art, concerned with arranging plants harmoniously in their surroundings, and as a science, encompassing the principles and techniques of plant cultivation. Because plants are often grown in conditions markedly different from those of their natural environment, it is necessary to apply to their cultivation techniques derived from plant physiology, chemistry, and botany, modified by the experience of the planter. The basic principles involved in growing plants are the same in all parts of the world, but the practice naturally needs much adaptation to local conditions. For the main history of garden development, see the article garden and landscape design: Historical development. the laying out and care of a plot of ground devoted partially or wholly to the growing of plants such as herbs, fruits, flowers, or vegetables. Gardening can be considered both as an art, concerned with arranging plants harmoniously in their surroundings, and as a science, encompassing the principles and techniques of plant cultivation. Planting and tending a garden next to a dwelling place is practiced not only for the spot of beauty, repose, and seclusion it creates, or for the food it provides, but also for the feelings of relaxation, anticipation, and contentment gained from the work involved. Many garden plants are grown in conditions widely different from their natural environments and have been selectively bred for generations. Gardening therefore requires protecting them from naturally growing weeds and cultivating them according to methods derived both from science and from practical experience under local conditions. Small home gardens became prevalent in the 19th century. Individual plants and flowers attracted increasing interest, and growers started to specialize, introduce exotic species, and compete in exhibitions. Private gardens have become smaller and less formal than those of earlier times. They may occupy extensive areas surrounding the house or may be as small as a window box or some pots on a windowsill. Labour-saving tools and new discoveries in plant physiology and pest control have encouraged the spread of horticulture both as a profession and as a relaxation and hobby. Designs for a garden area often incorporate a boundary (for example, a fence, wall, or hedge), paths, seats, and some focal point, such as a pool or piece of sculpture. The more or less permanent elements of a garden may include lawn, shrubs, vines, and trees. The lawn usually consists of grass, kept shorn close to the ground. Nongrass lawns may be planted with some variety of low-growing creeping plant. Shrubs and bushes growing up to about 20 feet (6 metres) require little labour, and some flowering varieties bloom for extended periods. Vines can soften the sharp lines of buildings and fences, provide shade over arbours, or cover slopes and terraces. Trees, furnishing protection and interest, have a range of sizes, shapes, and colours broad enough to suit any garden scheme. Transitory elements in a garden include the herbaceous plantsannuals, biennials, and perennialswhich die down each year, and the bulbous plants, which survive seasons unfavourable for growth and from which a new stem arises annually. The style of a garden depends on how it is laid out, where it is situated, and what plants are grown. A well-designed flower garden displays blends and contrasts of colours and forms. Shrubs and trees are placed first and the spaces for herbaceous plants and bulbs arranged around them. The design may include areas of blooms for both the summer and the spring. Woodland gardens have a less formal style. Trees are thinned but left in irregular groups; paths are winding; plants are those that grow naturally in the woods. Rock gardens are planned to look like a natural part of a rocky slope. The rocks, mainly of sandstone or limestone, are arranged to provide various exposures for sun-tolerant and shade-tolerant plants. A water garden may have a formal pool and fountains, or it may consist of an irregular-shaped pool containing water lilies and other vegetation surrounded by boggy soil for moisture-tolerant plants. Vegetable and herb gardens require sunny locations, and vegetable crops are most successful when they are rotated every three years or so. Rooftop gardens, window boxes, and indoor plants are increasingly popular in urban areas and can thrive well with the right choice of plants. Soil is the basic factor in plant cultivation. It consists largely of mineral particles derived from the breakdown of rocks and other substances and also contains organic matter. Plant roots penetrate spaces between the particles where air, water, and microorganisms circulate. Ideal garden soil is a clay and sand mixture, rich in organic materials and of the proper degree of acidity or alkalinity for the plants to be grown. The three chief elements that plants need for growth (other than light and water) are nitrogen, potassium, and phosphorus. Animal manures or composts of decayed plant matter can supply most growth requirements to the soil. Thorough watering is essential, furnishing the plants with needed moisture and making minerals available in solution. Many plants can withstand temperatures below freezing, but less hardy plants may have to be protected from cold weather by wrapping them or covering them with a mulch of leaves, soil, or ashes. Glass frames provide greater protection, and heated greenhouses permit plants to grow throughout the winter. Trees and shrubs sometimes require pruningcutting off branches or shootsto restrict the plant to a desired size and shape. Shrubs may flower more abundantly after pruning, and pruned fruit trees often yield larger and better fruit. New plants can be propagated either from seeds or from a part of the parent plant. Seeds of vegetables and annual plants are usually sown in the spring. Trees and bushes can be produced by a variety of propagation methods from parent shoots or buds. Two essential gardening tasks are the control of weeds and the protection of plants from pests and diseases. Chemical and biological weed killers can be effective, but hoeing and hand weeding are often necessary. Garden pests include some insects and mites as well as a number of mammals; diseases may be caused by fungi, bacteria, or viruses. Keeping a clean, well-ventilated garden and rotating crops can help to prevent some of these problems. Chemical control is widely used, though with some long-term environmental risks. Gardens in the world's temperate zones are generally more varied and successful than those of the tropics. Tropical gardens are able to maintain fewer herbaceous plants, and their dominant features tend to be flowering trees, shrubs, and climbers. In cooler climates the winter resting season enables many different plants and trees to thrive year after year. Additional reading History Short histories may be found in many of the larger gardening encyclopaedias. Fuller accounts include Christopher Thacker, The History of Gardens (1979, reprinted 1985); Anthony Huxley, An Illustrated History of Gardening (1978, reprinted 1983); Miles Hadfield, A History of British Gardening, 3rd ed. (1979); and Josephine Von Miklos and Evelyn Fiore, The History, the Beauty, the Riches of the Gardener's World (1969). Classics and good reading William Robinson, Wild Garden, 4th ed. (1894, reprinted 1977); Gertrude Jekyll, Wood and Garden (1899, reprinted 1983), Home and Garden (1900, reprinted 1982), and Colour Schemes for the Flower Garden (1908, reprinted 1983); Gertrude Jekyll and Lawrence Weaver, Gardens for Small Country Houses (1912, reprinted 1981); Henry N. Ellacombe, In a Gloucestershire Garden (1895, reprinted 1982), and In My Vicarage Garden and Elsewhere (1902); Maria Theresa Earle, Pot-Pourri from a Surrey Garden (1897); V. Sackville-West, V. Sackville-West's Garden Book, ed. by Philippa Nicolson (1968, reprinted 1983); Margerie Fish, We Made a Garden (1956, reissued 1983), An All the Year Garden (1958), Cottage Garden Flowers (1961, reissued 1980), and A Flower for Every Day (1965, reissued 1981); Karel Capek, Gardener's Year (1931, reprinted 1984; originally published in Czech, 1929); Christopher Lloyd, The Well-Tempered Garden, new rev. ed. (1985), The Adventurous Gardener (1983), and The Well-Chosen Garden (1984); and John Raven, A Botanist's Garden (1971). Reference sources A wealth of information can be found in the multivolume series The Time-Life Encyclopedia of Gardening. Douglas Reid, Botany for the Gardener (1966), is an account of principles underlying gardening practices; and Russel Page, The Education of a Gardener (1962, reissued 1985), is helpful in garden planning. See also D.J. Edwards, Gardening Explained (1969); and Hugh Johnson, The Principles of Gardening (1979). More substantial and detailed works include Christopher Briskell (ed.), The Royal Horticultural Society's Concise Encyclopedia of Gardening Techniques (1983); and Roy Hay and Patrick M. Synge, The Dictionary of Garden Plants in Colour, new ed. (1976). Garden types Lanning Roper, Successful Town Gardening (1957); Judith Berrisford, The Wild Garden (1966); Xenia Field, Town and Roof Gardens (1967); and Kenneth A. Beckett, David Carr, and David Stevens, The Contained Garden (1982). The principles of gardening Soil: its nature and needs Soil is the basic element in the cultivation of all plants, although soilless growth in water with or without gravel or sand, enriched with suitable chemicals (hydroponics) can be very successful. Soil consists of particles, mainly mineral, derived from the breakdown of rocks and other substances together with organic matter. In the pore spaces between the particles both water (containing dissolved salts) and air circulate. The air contains more carbon dioxide and less oxygen than does the atmosphere. Minute living organisms are also present in soil in immense quantities and are what make it alive. Plants must penetrate this pore space to reach much of their nourishment. The soil must be managed for fertility (the ability to supply plant nutrients) and physical condition. Nutrients must be supplied and released in forms available to the plant. Sixteen elements are necessary for plant growth. Three of these, carbon, oxygen, and hydrogen, are provided through water and air; the other 13 are provided through the soil. The elements required in relatively large amounts are called major elements: nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur. The minerals required in small quantities are called trace elements: iron, boron, manganese, zinc, molybdenum, copper, and chlorine. Soils can be roughly divided into three main types on the basis of their usefulness horticulturally, but many areas contain a mixture. Clays Clays, in which the particles are very fine, are called in horticulture heavy soils, because it is difficult to turn them over with a spade. They can be very fertile but tend to be lacking in good drainage, holding their water closely adhered to the soil particles; therefore, they cannot be worked when wet, and under pressure they tend to compact tightly, driving out the air. During drought they tend to become hard and even to develop large cracks so that they cannot be worked satisfactorily. Clay soils can be lightened with as much humus as can be dug into them. Humus may be any decayed organic matter, such as farmyard manure, leaf mold, or compost made from kitchen scraps and grass clippings. Types of gardens The domestic garden can assume almost any identity the owner wishes within the limits of climate, materials, and means. The size of the plot is one of the main factors, deciding not only the scope but also the kind of display and usage. Limits on space near urban centres, as well as the wish to spend less time on upkeep, have tended to make modern gardens ever smaller. Paradoxically, this happens at a time when the variety of plants and hybrids has never been wider. The wise small gardener avoids the temptations of this banquet. Some of the most attractive miniature schemes, such as those seen in Japan or in some Western patio gardens, are effectively based on an austere simplicity of design and content, with a handful of plants given room to find their proper identities. In the medium- to large-sized garden the tradition generally continues of dividing the area to serve various purposes: a main ornamental section to enhance the residence and provide vistas; walkways and seating areas for recreation; a vegetable plot; a children's play area; and features to catch the eye here and there. Because most gardens are mixed, the resulting style is a matter of emphasis rather than exclusive concentration on one aspect. It may be useful to review briefly the main garden types. Flower gardens Though flower gardens in different countries may vary in the types of plants that are grown, the basic planning and principles are nearly the same, whether the gardens are formal or informal. Trees and shrubs are the mainstay of a well-designed flower garden. These permanent features are usually planned first, and the spaces for herbaceous plants, annuals, and bulbs are arranged around them. The range of flowering trees and shrubs is enormous. It is important, however, that such plants be appropriate to the areas they will occupy when mature. Thus it is of little use to plant a forest tree that will grow 100 feet (30 metres) high and 50 feet across in a small suburban front garden 30 feet square, but a narrow flowering cherry or redbud tree would be quite suitable. Blending and contrast of colour as well as of forms are important aspects to consider in planning a garden. The older type of herbaceous border was designed to give a maximum display of colour in summer, but many gardeners now prefer to have flowers during the early spring as well, at the expense of some bare patches later. This is often done by planting early-flowering bulbs in groups toward the front. Mixed borders of flowering shrubs combined with herbaceous plants are also popular and do not require quite so much maintenance as the completely herbaceous border. Groups of half-hardy annuals, which can withstand low night temperatures, may be planted at the end of spring to fill gaps left by the spring-flowering bulbs. The perpetual-flowering roses and some of the larger shrub roses look good toward the back of such a border, but the hybrid tea roses and the floribunda and polyantha roses are usually grown in separate rose beds or in a rose garden by themselves.