Crop of cucumbers in greenhouse built under the supervision of Syrian agronomists trained by FAO horticulturists. Cucumbers are very susceptible to fluctuations in temperature and heating in necessary for winter production. - - 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.