Horticulture is the art of cultivating plants in gardens to produce food and medicinal ingredients, or for comfort and ornamental purposes. Horticulturist are agriculturist who grow flowers, fruits and nuts, vegetables and herbs as well as ornamental trees and lawns. When you look at the temperature regions, temperate zones for horticulture cannot be defined exactly by lines of latitude or longitude bust are usually regarded as including those areas where frost in winter occurs, even though rarely.Thus most parts of Europe, North America, and northern Asia are included, though some parts of the United States, such as southern Florida, are considered subtropical. Propagation, the controlled perpetuation of plants, is the most basic of horticultural practices. Its two objective are to achieve an increase in numbers and to preserve the essential characteristics of plant. Propagation can be achieved sexually by seed or asexually by utilizing specialized vegetative structure or by employing such techniques as cutting, layering, grafting and tissue culture. The most common method of propagation for self-pollinated plants is by seed. In self-pollinated plants, the sperm nuclei in pollen produce by a flower fertilize egg cells of a flower on the same plant.

Plant breeding, the systematic improvement of plants through the application of genetic principles, has placed improvement of horticulture plants on a scientific basis.