Greenhouse tomatoes being sorted and packed into boxes for market. - - Out of Season Vegetable Production. In 1977, the Government of Syria, with the assistance of FAO/UNDP, began the construction of plastic greenhouses at El Hannade and Amrit. These were to demonstrate out-of-season production of vegetables, which previously had been imported at very high prices. Tomatoes, cucumbers, courgettes, peppers and aubergines were raised with great success. Training in greenhouse culture, as well as initial planning and layout, were provided by specially sent horticulturists.