ADAPTATION OF THE HYDROSOLARIC GREENHOUSE FOR CULTIVATION OF ROSES FOR CUT FLOWERS

The hydrosolaric greenhouse is a closed structure that absorbs solar energy during the day, stores it in a water reservoir, and utilizes it at night.
This closed greenhouse allows enrichment of the atmosphere with CO₂ throughout the day.

During the day the relative humidity of the greenhouse depends on the temperature of the water reservoir.
Since high relative humidity decreases cut flower quality, a relative humidity of approx. 80% was the objective.
This was obtainable when water temperature was maintained at 20°C and the greenhouse air at 25°C. High quality flowers of ‘Mercedes’, ‘Yaguar’ and ‘Sonia’ were obtained under these conditions, and when the atmosphere was enriched with 1000 ppm of CO₂, the yield was approximately 50% higher than that obtained in nearby commercial greenhouses.

In order to obtain healthy plants, they have to be kept dry during the night.
To achieve this, the following procedures were adopted: (a) One third of the greenhouse air volume was exchanged with outside air every 2 hours; (b) turbulence in greenhouse air was obtained with electrical fans of 2 W-m^-2 of floor area; and (c) a porous screen that absorbs long-wave radiation was raised automatically and remained spread throughout the night.

I International Symposium of the Research and Cultivation of Roses

N. Zamir, G. Ginzburg, A. Arbel, N. Levav, S. Gilad, A. Ackerman, A. Hagiladi, N. Levy

https://doi.org/10.17660/ActaHortic.1986.189.18