In the present work two different irrigation frequencies were tested in order to
evaluate the effect the irrigation frequency on rose crop fresh and dry weight, on leaf area
and on flower production and quality. Irrigation was based on solar radiation and was
performed when accumulative solar radiation outside the greenhouse reached 470 kJ m-2
(high irrigation frequency) and 940 kJ m-2 (low irrigation frequency). The amount of
water applied was 0.2 mm and 0.4 mm for high and low irrigation frequency, respectively.
From the production point of view, the results showed that irrigation frequency
affected to some extend the production (number of cut flowers) and the cut flower fresh
and dry weight since the total values of the abovementioned parameters observed were
slightly higher for the plants irrigated with a high frequency than for those irrigated with a
low frequency. However, for all cases, it was found that there were no significant
differences between the two treatments.
Measurements were carried out for 100 days and started only 60 after planting.
From the water use efficiency point of view, it seems that the higher irrigation frequency
improved the biomass production and thus increased the greenhouse water use efficiency
since for the same amount of water applied, more biomass was produced. However,
continuation of the measurements for more than 160 days after planting or when crop is in
full production stage would help to discriminate the above mentioned differences.