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Research article2009Peer reviewedOpen access

Light integral as an indicator of water use in commercial greenhouse nurseries

Lofkvist, K.; Larsen, R.; Englund, J. -E.; Alsanius, B. W.


Irrigation strategies in pot plants of Kalancho blossfeldiana were studied in two commercial greenhouse nurseries by continuous weighing of plants on a high-precision balance. The objectives were to study actual irrigation strategies implemented by growers and to evaluate the method of continuous weighing as a potential tool for future irrigation management. Mean values of temperature, relative humidity, light, and weight were recorded every five minutes using data loggers. The change in weight over time was estimated and related to the calculated total canopy surface area of the studied plants. The rate of weight change was then statistically tested in relation to the recorded external factors. The factor with the strongest effect on total water-consumption rate over time was the light integral. As expected, water consumption was also affected by temperature and humidity, as well as the time of day. Although the growers indicated clear irrigation strategies, the study showed that these were not implemented in a true sense or correlated to the information available in greenhouse climate computers. The study also indicated that a high-precision weighing balance might be an important tool for future control of plant growth and plant architecture through irrigation in the pot plant industry.


Canopy surface; irrigation regime; Kalancho blossfeldiana; light integral; plant weight; pot plants

Published in

Acta Agriculturae Scandinavica, Section B - Soil and Plant Science
2009, Volume: 59, number: 4, pages: 326-334
Publisher: Taylor & Francis: STM, Behavioural Science and Public Health Titles

      SLU Authors

      • Larsen, Rolf Uno

        • Horticulture, Swedish University of Agricultural Sciences