CO₂ CONCENTRATIONS ON DUTCH HOLDINGS WITH ROSES

In order to know which CO₂ concentrations are prevailing under Dutch circumstances in the course of a year a recording of the CO₂ concentration was performed on some holdings with roses.

Three types of glasshouses and two sources of CO₂ were selected.

The opening of the ventilators and the position of the CO₂ valve were also recorded.

During 30 to 50% of the daytime the CO₂ level was found to be below ambient.

The percentage of CO₂ deficient hours is different for the various months of the year.
It is low in winter and high in summer.

From figures 3 and 4 it must be concluded that not only the amounts of light determine the difference between winter and summer as spring and fall data are shifted from each other.

Clearly with respect to deficient hours also outdoor temperature has an influence because it determines whether the mainburner is on or off.

I International Symposium of the Research and Cultivation of Roses

G. Hey

https://doi.org/10.17660/ActaHortic.1986.189.19