“Gerbera: Growing in Balance” was a research project to support the reduction of energy and CO2 consumption in the cultivation of Gerbera. The varieties Pre-Semmy, Rich, Whisper and Suri were grown in three glasshouses with different treatments: “Cool Cultivation” (15°C temperature; 90 μmol light, day length 13 hour in winter); “Practice” (temperature depending on day light integral, 100 μmol/m2s light, day length 11.5 hours) and “Light Dependent” (temperature depending sharply on day light integral, 90 μmol/m2s light, day length 13 hours in winter). The day light integral was kept equal in all treatments, regardless the difference in light intensity and day length in the winter. For flower quality and energy use “Cool Cultivation” was the best treatment, but required the most kg / m² of CO2. Whisper and Suri produced more flowers / m2 in the treatment “Light Dependent” but flower weights were low. Pre-Semmy and Rich gave more flowers in the treatment “Practice”, but spalkes were weak in May and June. The 13 hour day length in winter was not detrimental to production or quality. Light sum, day length and daily temperature are the three buttons to control the plant balance for optimum production and quality. The project was Funded by the Program “Greenhouse as Energy Source” (Ministry of Economic Affairs and LTO Glaskracht) and the Knowledge Cooperative Gerbera.