horticulture, Branch of agriculture concerned with the cultivation of garden plants—generally fruits, vegetables, flowers, and ornamentals such as plants used for landscaping (see landscape gardening). Propagation, the controlled perpetuation of plants, is the most basic horticultural practice. Its objectives are to increase the numbers of a plant and to preserve its essential characteristics. Propagation may be achieved sexually by use of seeds or asexually by use of techniques such as cutting, grafting (see graft), and tissue culture. Successful horticulture depends on extensive control of the environment, including light, water, temperature, soil structure and fertility, and pests. Two important horticultural techniques are training (changing a plant’s orientation in space) and pruning (judicious removal of plant parts), used to improve the appearance or usefulness of plants. See also floriculture.