Ethanol treatment induces compact growth in Kalanchoë

Compact growth is a major quality characteristic for the attractiveness and transportation of Kalanchoë, one of most economically important potted plants in Europe. In the present experiments, we examined the possibility of using ethanol as an alternative plant growth regulator. We compared using either an ethanol spray or an ethanol watering treatment during standard cultivation of several Kalanchoë species and varieties. The results of the present study demonstrated that watering the plants with an ethanol solution was more effective than the ethanol spray treatment. All tested genotypes showed a correlation between the ethanol concentrations used for watering and the internode lengths internode after ethanol watering. However, high ethanol concentrations (more than 2%) led to leaf damage and delayed flower development in some genotypes. The use of ethanol as a growth regulator for ornamentals has several advantages. Ethanol is a biodegradable molecule that is inexpensive, easy and safe to apply, and non-toxic in the concentrations required.