Gerbera plant growth model
In a desktop research of Wageningen University& Research Center - Greenhouse Horticulture the physiology and anatomy of the Gerbera (African Daisy) has been studied in preparation of the development of a plant growth model. From this research Gerbera is found to be a quantitative short day plant. This means that fewer flowers are produced when nights shorten. Although flowering is stimulated by artificial lighting, for cultivars susceptible to a short day treatment supplemental lighting is only beneficial during a short days period. Assimilation lighting during the winter does have positive effects on the quality and production, but more than when they are exposed to artificial lighting for more than 12 hours a day, this results ina decline in production after 5 to 6 weeks.

There seems to be a correlation between the number of leaves and the amount of flowers formed, but none was found between the number of leaves formed and the number of actual stems formed. This may be due to the complexity of the combined effects of light and temperature on flower development, whereby day length and light intensity seem to play contradictory roles.

Relatively high temperatures and low light levels stimulate vegetative growth, resulting in more leaves and fewer flowers (because of flower abortion). At low temperatures, less leaves are formed (low leaf separation speed) and plants behave more generative and form more flowers. Because of the Gerbera's rosette growth habit, substrate temperature may also affect production.
The information gained in this research will be used to further develop the plant growth model of Gerbera.

Source: WUR – Greenhouse Horticulture