Good internal air circulation in the greenhouse at night and ventilation during the day are essential. High humidity appears to contribute to flower stalk stretching. Light Gerberas require high light intensities for good-quality plants and high flower bud numbers. For this reason, they are mostly produced in the spring and summer, with the greatest amount of production for the spring market. Plants grow best in full sun during the fall, winter, and spring.
Plants receiving too little light have pale green, stretched foliage and long, weak flower stems.
Plants receiving too much light have compact, slightly yellow foliage with short flower stems often hidden in the foliage. Gerberas appear to respond only slightly to photoperiod. Short days tend to speed flower production, while long days delay flowering. However, many growers produce gerberas with no photoperiod control. Some growers extend the photoperiod from October through March for 4 weeks only to get more vegetative growth before flowering.