As plants grow they are replanted into individual plastic containers called “cans” (typically 2 or 3 times during the early growth cycle). New plants are started in a specialized medium using one of four standard methods: cuttings from mature plants, tissue culture, seeds and grafting. Typical operations at a large wholesale nursery specializing in container-grown outdoor bedding and ornamental plants consist of four stages: Many of these hazards are common for the two operations. The hazards discussed below are limited to ergonomic hazards in nursery work and pesticide hazards in greenhouse work. Nursery and greenhouse workers are exposed to a variety of hazards, including skin irritants, dust, noise, heat stress, musculoskeletal disorders (sprains and strains), pesticides and injuries related to vehicles, machines, slips and falls and electricity. The greenhouse operation requires the control of temperature, humidity and ventilation, using artificial heat sources, exhaust and inlet fans, shading (such as with movable slats or netting), cooling equipment (such as wet-pad or evaporative cooling), humidification and climate-control equipment (Jones 1978). The last is protecting the plants from environmental stress, including snow, rain, hail, high winds, birds, small animals and insects. Another is for heating within an enclosure. One is to let sunlight in for the plants. Covers can vary from clear to opaque, and they serve three purposes. Polycarbonate, which withstands breakage from thrown objects, and the flexible plastics require frequent replacement. Flexible plastic covers include polyethylene, polyvinyl chloride and polyester. Rigid plastics used as covers include fibreglass, acrylic and polycarbonate. The plastic can be either rigid or a flexible film. Covers include glass or plastic, and in some parts of the world, the glass-covered house is called a glasshouse. In the Ukraine, 60% of the greenhouses have masonry block walls. Side walls or siding can be made from a variety of materials including plywood, aluminium, wood or vinyl. The framing materials for greenhouses include wood, aluminium or a combination of steel pipe and wood. It provides good exposure to winter sunlight, drainage and wind protection. The gable (equal sloping roof) greenhouse is typical. ![]() For example, in the Ukraine, the total area of greenhouses has grown from 3,070 hectares (ha) in 1985 to 3,200 ha in 1990 to an estimated 3,400 ha in 1995 (Viten, Krashyyuh and Ilyna 1994). Greenhouse operations have expanded in temperate climates. The controlled environment within a greenhouse is advantageous to those who wish to grow crops year-round, regardless of seasonal conditions outdoors. Greenhouses provide a controlled environment for plants and are used for a variety of purposes, which include growing rare and exotic plants, protecting producing plants (such as flowers, tomatoes and peppers) from winter weather and starting seedlings. Few workers belong to labour organizations in this industry, and most workers are employed directly by the enterprise rather than by farm labour contractors. Nursery work is considered a comparatively good job by most agricultural workers because it is year-round, comparatively well-paid and frequently includes workers’ compensation insurance and employee health benefits. Similar situations exist throughout the world. Wages are low for most jobs, and there is a labour surplus. Most speak Spanish only or as a primary language and have little or no formal education. ![]() The majority of these workers are not migrant, but are settled in local communities with their families (Mines and Martin 1986). ![]() As with much of western US agriculture, the employee population is dominated by workers from Mexico or other Central American countries. In California, where there are more than 3,000 commercial nursery operations, nursery crops are a high value-per-acre commodity, ranking fifth in state farm income. The plant nursery industry constitutes a large and growing sector of agriculture. The nursery industry grows plants for the replanting market, but greenhouses are also used for growing crops for seasonal markets, such as tomatoes during the freezing months of winter.įigure 1. Setting coffee plants in a nursery in Cote d’Ivoire Typical nursery crops are trees and shrubs, and the typical greenhouse crops include flowers, vegetables and herbs. Many plants grown inside during harsh growing conditions are grown outside in favourable weather conditions. Hardy plants are grown outside, and the less hardy plants are propagated and raised inside, typically in greenhouses, to protect them from cold temperatures or too much solar radiation or wind. The nursery industry raises plants for the replanting market (see figure 1).
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