Greenhouse design for vegetable production in subtropical climate in Taiwan

In Taiwan open field vegetable production is threatened by subtropical climatic disasters, such as high wind speeds and heavy rainfall, which can cause the destruction of whole crops. Next to that vegetable production is threatened by pests and diseases resulting a high need for pesticides. Greenhouse production systems are able to provide protection for the crop. However, in current protected tomato production in Taiwan yields are extremely low (max. 4 kg cherry tomato m-2 per season, though with high Brix). Next to a deficiency in modern crop management, there is a lack of knowledge of what is the optimum greenhouse design for vegetable growing in Taiwan. Greenhouse design has been shown to be a multifactorial problem, which can be approached with a systematic design method (Van Henten et al., 2012). The method is based on the use of different models, which predict a suitable greenhouse design. The local climatic conditions (outside radiation, temperature, humidity, wind speed) are used as input for the greenhouse climate model, which is used to evaluate different greenhouse designs and technologies. The climate and crop growth inside the green¬house can be simulated. These data serve as input to an economic model, which can be used to come to the economic suitable greenhouse design. This greenhouse design approach was applied for Taiwanese climate conditions, which are characterised by a radiation sum of 6 GJ m-2, high temperatures up to an average maximum of 35°C and high humidity levels up to 100%. The greenhouse climate model of De Zwart (1996) and the crop model of Vanthoor (2011) were used for evaluation of different technologies, economic data was collected in Taiwan and used as input for the economic model