Effect of long days and short days on the growth of young Kalanchoe
Gartenbauwissenschaft 31(3): 429-436
Kalanchoe plants were subjected to long day or short day, and to strong supplementary light before and after the 2nd leaves had expanded. During this stage, no flower induction by short days took place, but day length influenced plant shape. After the different treatments, the plants were kept under long day conditions. During the early growth period short days reduced growth in the following long day condition. The difference in size between short day and long day individuals increases after different treatment. The sooner the short day period was stopped, the lower was the growth inhibition. In the early growth period, strong supplementary light effected long day individuals more than short day individuals. Growth promotion by strong supplementary light is relatively weaker than by long day treatment.