short-day plant A plant in which flowering is favoured by short days and correspondingly long nights. There are two groups of such plants, some species in which there is an absolute requirement for these conditions for the onset of flowering, and other species in which flowering is merely hastened by them. In fact, however, the term is somewhat misleading in that the critical factor is the period of darkness and short-day plants require a night of more than a minimum duration. Horticulturists exploit this, for example, by exposing chrysanthemums to a brief flash of light during the night to delay flowering until Christmas.

short-day plant A plant in which flowering is favoured by short days and correspondingly long nights. There are 2 groups of such plants, some species in which there is an absolute requirement for these conditions for the onset of flowering, and other species in which flowering is merely hastened by them. In fact, however, the term is somewhat misleading, in that the critical factor is the period of darkness and short-day plants require a night of more than a minimum duration. Horticulturists exploit this by exposing chrysanthemums to a brief flash of light during the night to delay flowering until Christmas.

short-day plant A plant in which flowering can be induced or enhanced by short days, usually of less than 12 hours of daylight. Examples are strawberry and chrysanthemum. See photoperiodism. Compare day-neutral plant; long-day plant.