Defining Horticulture

Defining Horticulture, Horticultural Products and Horticultural Science

The aim of the ISHS is " promote and encourage research and education in all branches of horticultural science and to facilitate cooperation and knowledge transfer on a global scale through its symposia and congresses, publications and scientific structure." Membership is open to all interested researchers, educators, students and horticultural industry professionals.

Horticultural Products

Horticultural products include all products, raw or processed, that arise from the horticultural industry. This broadly inclusive definition is appropriate and even necessary in a time when traceability from the producer to the ultimate consumer is of growing interest to government and industry. Products from horticultural industry that go to market still respiring (fresh produce) are clearly horticultural products. When juiced, sliced or pureed, fermented, frozen, preserved, canned, dried, irradiated, or used in an ornamental construct (such as a flower arrangement) they remain, in our view, a horticultural product. However, when a horticultural product becomes a major ingredient of another manufactured item the categorization becomes more complex. Thus, when apples are used to make apple pie or yogurt is fortified with fruit, the product can be considered both a horticultural product and a bakery or dairy product.

Horticultural Crops

But to use this definition of a horticultural product, it is necessary to know what crops are appropriately assigned to horticultural industry. It is generally accepted by researchers and educators in horticultural science that horticultural crops include:

  • tree, bush and perennial vine fruits;
  • perennial bush and tree nuts;
  • vegetables (roots, tubers, shoots, stems, leaves, fruits and flowers of edible and mainly annual plants);
  • aromatic and medicinal foliage, seeds and roots (from annual or perennial plants);
  • cut flowers, potted ornamental plants, and bedding plants (involving both annual or perennial plants); and
  • trees, shrubs, turf and ornamental grasses propagated and produced in nurseries for use in landscaping or for establishing fruit orchards or other crop production units.

Sometimes the horticultural plant is used by an animal to produce the crop. Honey is a good example and is often considered to be a horticultural product. Raw silk is produced by silkworms feeding on mulberry trees (which also produce an edible fruit) but silk is not a horticultural crop. In Canada both honey and maple syrup are classed as horticultural crops. Cultivated or gathered mushrooms (edible fungi) are most often classed as horticultural crops.

Some Horticultural Industry Descriptors

Like the other divisions of plant agriculture, horticulture is practised across cool temperate to tropical latitudes and over a wide range of elevations and climatic conditions. However, it differs from agronomy in a number of significant ways – although it must be recognized that some crops can be classed as both horticultural or agronomic depending on use.

For example, there are soybean cultivars suitable for fresh consumption and grown intensively in market gardens, especially in Asian countries, but soybeans are more commonly grown extensively as a field crop for oil and protein production.

Sweet corn produced for fresh market, canning or freezing is horticulture whereas maize grown for grain or forage is agronomy.

Horticultural cropping systems are intensive in terms of investment, labour requirements and other inputs and are often (but not always) confined to smaller parcels of high quality land. Protected cultivation (e.g., glasshouses or plastic tunnels) and irrigation are common. Accordingly, the products of horticultural enterprise usually have a much higher per unit value than crops grown in less intensive systems. Still, some high value horticultural products are gathered from fields or forests. Wild blueberries and Brazil nuts are two examples. Regardless of scale or intensity, horticulture is not the production of pasture or forage for feeding animals.

Growing grains, pulses or oilseeds for feed, food or industrial use is not horticulture nor are systems growing plants for fibre production (e.g., cotton, flax and hemp). Forests or plantations growing trees for industrial products (e.g., for fibre or building materials, latex production for rubber manufacture, oil production for food or industry – like oil palms) are not horticulture. The production units for these kind of systems have English names like pastures, range, forests or fields, whereas horticultural production units are called gardens, orchards, groves, vineyards, greenhouses, nurseries, and sometimes plantations.

Horticultural Science

Clearly, horticultural science addresses the needs and issues of horticultural industry as described above. However, it includes much more. We often use terms like environmental horticulture or urban horticulture to capture a second realm that more specifically addresses environmental enhancement issues. Within this realm we more often train our graduates to perform a service than deliver a consumable product, but it is not correct to assume that these activities have less economic value. Environmental or urban horticulture supports activities like home gardening, landscaping (in this context tending one's lawn is considered a horticultural activity), arboriculture, and interior decorating with plants.

These activities are often used in a human health construct we know as horticultural therapy. Urban parks, gardens and street trees are considered essential for creating a good living environment in communities around the world and are tended by the Horticulture Department of many cities and towns.

Thus, horticulture has an important "quality of life" component for which our citizens spend great amounts of time and money. Another realm of horticultural science with great environmental and commercial importance involves the collection, preservation, organization, characterization and improvement of horticultural plant genetic resources.

Thus, plant exploration, botanical gardens and arboreta, naming authorities, gene banks, genomics and plant breeding are the domain of many people employed in horticulture. In summary, horticultural science exists to build and maintain human knowledge, skills and biological resources in support of horticulture industry and environment enhancement.

Horticultural scientists explore and explain the many contributions of plants to a healthy environment for human life and well being. Horticultural science must be deemed an essential life science.