The ratio of C-N is usually quite high as the impetus for the formation of flowers. However, many found the kinds of plants that require a trigger so that the flowers appear. These triggers can be either a low temperature for a long time (vernalisasi),
length (duration) shines (fotoperiodisme), and water shortages (drought). Wheat bread type winter (winter, because it was planted late winter) will not bloom if not experiencing winter in the stages of growth and development. Pigeon orchid flower when subjected to bring up a cold night. A variety of jute cultivars are fotoperiodik until the time of planting was vital in determining the harvest. Coffee plant requires dry period is known for about two months and was followed by rain to trigger the formation of flowers.
Studies conducted on Arabidopsis thaliana, a plant model, showing the works of the ABC Theory in the formation of flowers. A substance needed to form the leaves of the calyx (sepal) and Corolla (petal). B substance is required in the formation of petals and Stamen (stamen). C the substance is required for the formation of Stamen and green fruit (carpellum, as the framers of the pistil).