Based on positive effects reported on using diffuse covering materials in a number of studies in the Netherlands, it can be expected that diffusive cover gives much better harvests than a cover with clear glass in sunny zones i.e. Gulf region. Scattering the direct solar radiation into multiple directions gives an improved homogeneity of light in the crop, which likely improves production.
Experimental history
- Seed sowing: 7 Nov. 2016
- Transplanting: 26 Nov. 2016
- Plant Density: 2.5 plants per m²
- Harvesting Period: 20 December 2016 – 12 March 2017 (12 weeks)
- Number of Harvests: 28
This project aims to compare the production between two greenhouse compartments, only differing in the covering material while the overall light transmission is equal. The results
were analyzed in terms of production and water use for cooling.
- Two covering types: Clear Glass and Diffusing Glass covered greenhouse with an average overall transmissivity is 60%
- Two cucumber varieties: Khalid and Waleed (Enza seeds)
No significant difference found between clear and diffuse glazed greenhouse compartment in term of cucumber fruit yield
| Clear Glass | Production | |
|---|---|---|
| Khalid | 17.2 kg/m² | Average 210 gram/day |
| Waleed | 17.9 kg/m² | Average 218 gram/day |
| Diffuse Glass | Production | |
|---|---|---|
| Khalid | 17.0 kg/m² | Average 208 gram/day |
| Waleed | 16.1 kg/m² | Average 196 gram/day |
Recommendation
A diffusive greenhouse cover gives better working conditions (smaller light/dark contrasts) but does not affect cucumber production. This holds of course when the diffusiveness is the only different factor, which means that the overall light transmission is the same.