'Green Shell Early' water bamboo is conventionally cultivated from January to October annually in Taiwan. The edible galls could be harvested in April-June and July-October, designed as the first and the second harvest periods, respectively. Earlier planting could result in a physical disorder named as ＂stunting disease.＂ Based on the experiment conducted inside growth chambers, short daylength favors gall formation in regardless of shoot age, and the sensitivity to short daylength of gall formation was stronger in younger plants. It indicated that ＂stunting disease＂ may resulted from the early formation of gall in plants when they are too young under short daylength. Thus the stunting disease could avoided by night lighting at young plant age when planted early. By this way young plants were planted 30 d earlier than normal and supplied with 60 d night lighting (12 h d^(-1)). Normal edible galls could be harvested about 20 d earlier than the conventional cultivation. Cutting off all the shoots after the second harvest may result in synchronically shoot regeneration. Therefore, a third harvest period could be created in winter by the combination treatment of shoot cut off and night lighting after the second harvest. The harvest time could be advanced or delayed by decreasing or increasing the duration of night lighting. Thus, the harvest period could be scheduled more accurately. A year-round production system could be achieved by applying the three-harvest-period cultivation technique in different subsections in the field conditions.