A nursery is a place where plants are propagated and grown to usable size. There are retail nurseries which sell to the general public, wholesale nurseries which sell only to other nurseries and to commercial landscape gardeners, and private nurseries which supply the needs of institutions or private estates. Some retail and wholesale nurseries sell by mail.
Nurseries grow annuals, perennials, and woody plants (trees and shrubs). These have a variety of uses: decorative plants for flower gardening and landscaping, garden vegetable plants, and agricultural plants.
Nurseries often grow plants in a greenhouse, a building of glass or in plastic tunnels, designed to protect young plants from harsh weather (especially frost), while allowing access to light and ventilation. Modern greenhouses allow automated control of temperature, ventilation and light and semi-automated watering and feeding. Some also have fold-back roofs to allow "hardening-off" of plants without the need for manual transfer to outdoor beds.
Most nurseries remain highly labour-intensive. Although some processes have been mechanised and automated, others have not. It remains highly unlikely that all plants treated in the same way at the same time will arrive at the same condition together, so plant care requires observation, judgement and manual dexterity; selection for sale requires comparison and judgement. A UK nurseryman has estimated (in 2003) that manpower accounts for 70% of his production costs. The largest UK nurseries have moved to minimise labour costs by the use of computer controlled warehousing methods: plants are palletised, allocated to a location and grown on there with little human intervention. Picking merely requires selection of a batch and manual quality control before despatch. In other cases, a high loss rate during maturation is accepted for the reduction in detailed plant maintenance costs.
Business is highly seasonal, concentrated in spring and autumn. There is no guarantee that there will be demand for the product - this will be affected by temperature, drought, cheaper foreign competition, fashion, etc. A nursery carries these risks and fluctuations.
Annuals are sold in trays (undivided containers with multiple plants), flats (trays with built-in cells), peat pots, or plastic pots. Perennials and woody plants are sold either in pots, bare-root or balled and burlaped and in a variety of sizes, from liners to mature trees.