Abstract: The naturally ventilated greenhouse (NVGH) and fan- and pad-cooled greenhouse (FPGH) were designed and constructed for conditions in Bangalore, Karnataka, India. Gerbera crop was cultivated in both greenhouses and temperature and relative humidity (RH) were recorded at 10.00, 13.00 and 16.00 h. The temperature in NVGH could be brought down very near to ambient temperature during hot and dry months by proper irrigation. The maximum temperature during the year in NVGH was 36.6 degrees C when the ambient temperature was 35.4 degrees C and RH 28.4% at 13.00 h in April. The maximum build up of temperature of 2.5 degrees C was recorded during rainy and cloudy days when the ambient temperature was low and RH was high. The average build up of humidity on a yearly basis in NVGH was 1.5% above the ambient RH. The drop in temperature up to 8.2 degrees C was observed in FPGH in April when the ambient temperature was very high (35.4 degrees C) and ambient RH was very low (28.4%). The maximum temperature of 30.1 degrees C
