Short Day Plants

a. Short Day Plants (SDP) : Short Day Plants (SDP) typically flower in winter or late summer, when the length of the day is shorter than a critical photoperiod -- the specific day length above or below which flowering is triggered for that species. SDPs are more accurately described as long night plants, because what they actually require is a sufficiently long, uninterrupted period of continuous darkness; if that dark period is interrupted even by a brief flash of light, an SDP will fail to flower. Examples of short day plants in …