Itzhak Secker-Esquire
State Greenhouse, Plasticulture and Climate
Control Extension Specialist - Israel

Protected cultivation in the Mediterranean area is being affected by two main factors: the European market’s demands and the weather. In this area there are more than 119.340 hectares (298,350 acres) of greenhouses with annual increase of 5-7%. The greenhouse’s types are ranges from simple walk-in tunnel (6-8 m wide) with natural ventilation to high-equipped greenhouses with the latest technology such as climate control systems and soilless culture. All types of crops are grown under protected condition, vegetable as well as fruits.

Weather - The high radiation conditions in autumn and winter, the mild winter temperatures and the climatic stability influence by the vicinity of the sea have been described as the main advantage of protected cultivation in the Mediterranean area (Short and Bauerle, 1986).

The shift in the greenhouse vegetable production from the cold part of Europe to the Mediterranean area took place during the energy crisis in the mid 70's. The relatively low-cost plastic greenhouses enable the production of low cost, out of season commodities (Montero, 1988).

Since most of the greenhouse know-how and technology is based and originated from countries like the Netherlands, many changes needed to be made to adjust it to warm and dry climates. Plastic houses have replaced glasshouses. Walk-in tunnels are representing 40-60% of the plastic houses mainly for fall and early spring production.

Natural ventilation, which is the common ventilating system in cold areas, is not suitable enough for year round production in warm growing areas. Therefore, cooling systems based on adiabatic principles (evaporating cooling) were adopted to increase humidity and to create a favorable condition for producing quality produce and expanding the growing season.

In order to meet the new European quality standards and the market’s demand growers are taking measures in the following fields: expanding the growing season, diversifying the production and introducing new crops, reducing chemicals use, cooling and venting systems, saving in labor cost, soilless culture, water drainage recycling, climate control and automation, quality, and management control.

Proceedings - Table of Contents