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Most banana screenhouses are currently equipped with transparent screens, with a nominal shading of 8–15%. Two types of screens are widely used, woven or knitted, which differ in their texture and hence in their radiative and aerodynamic properties. These differences may induce different micro-climatic conditions and hence different atmospheric water demand, plant response and yield. We have investigated four types of screens based on different shading levels (8%, 10% or 13%) and different screen textures (woven or knitted). A large commercial banana plantation in Northern Israel was covered with patches of the four different screen types, each in 4–5 replicates, randomly located. Air velocity, temperature, humidity and net radiation were measured simultaneously below two out of the four screen types: the 10% woven and 10% knitted. The results showed that both the net radiation and air temperature were similar under these two screens. Nevertheless, under the knitted screen the horizontal mean air velocity was 18% higher and the specific humidity 8% lower than under the woven screen. Leaf lamina tearing (typical wind damage) and estimated reference evapotranspiration were higher under the knitted screen; the latter mainly during the fall–winter season. However, the horticultural measures of flowering and fruit yield characteristics were the same under all four screen types, with results typical of screenhouse banana plantations in this region. Hence, the results suggest a potential increase in water use efficiency under the woven as compared to the knitted screen.

A desuckering experiment with cultivar ‘Williams’ banana was established at Burgershall Research Station in the subtropical Eastern Transvaal. Unwanted suckers were excised when they attained a height of 300 (control), 500 or 800 mm, leaving one sucker per mat as the ratoon follower. A fourth treatment entailed desuckering at a height of 300 mm, but with a large nursery sucker left on the mat for later excavation. In the plant crop there was no significant reduction of bunch mass or yield per annum due to desuckering at 800-mm height. However the selected first (R1) and second (R2) ratoon followers which were competing with large unwanted suckers produced smaller bunches, an extended cycle time and lower yield per annum. In the R1 and R2 cycles, the yield reductions with 500-mm desuckering were 8.3 and 9.1%, whereas for 800-mm desuckering yield was reduced by 16.9 and 17.5%, respectively. No treatment differences occurred in the number of R1 suckers excised per mat. The presence of a large nursery sucker in addition to the follower decreased yield by 7.9 and 12.6%, respectively. Leaf area on an 800-mm sucker was 39 times greater than for a 300-mm sucker. Early desuckering of small suckers is recommended to improve yields and reduce labour costs.

Provision and soil covers in a ‘Robusta’ banana plantation considerably reduced consumptive use of water and number of irrigations needed throughout the period of crop growth. Consumptive use ranged from 1024 mm under 800-gauge thick black polyethylene cover at 60% depletion of available soil moisture to 1560 mm under no cover treatment at 20% depletion. There was a perceptible increase in water-use efficiency under soil covers at low available soil moisture depletion levels. Soil covers reduced the periodic crop coefficient values compared with bare soil, indicating the reduced (23–33%) water requirement of banana plants under soil covers. High crop coefficient values recorded up to 5 months after planting indicated high consumptive use of water during that period. Using the crop coefficient values and corresponding period reference crop evapotranspiration, periodic water requirement of ‘Robusta’ banana for profitable production could be estimated.