**2. Material and methods: low-cost and climate-smart irrigation technology**

The experiment was carried out in northern Ethiopia and the results from this field work served as the data for several theses done at the University of Mekelle. The water seeps out through the micro-pores of the clay pots with relatively slow flow and larger surface wetting time, and thus promotes a greater area of coverage around the roots of plants. Contrarily, perforated clay pots leak water faster through the macro- and micro-pores and have relatively shorter wetting time and smaller area coverage.

On the other hand, the difference between perforated bars and round ones was simply the shapes of the pots which has to do with the area of coverage along the rows of the Swiss chard plant. Round types of pots were not as suitable as bar types (of the same volume) for rows of Swiss chard crops due to their wetting area coverage along the two sides of the bar.

Therefore, among the tested clay pot designs, the bar-shaped perforated clay pot designs were evaluated as best in terms of biomass yield and economic water-use efficiency. The water-use efficiency, economic aspects, and biomass for the perforated bar clay pot design were better than that of the bucket irrigation system. The other advantages of perforated bar clay pots over the bucket type is that the water source is inside the soil thus evaporation is almost zero and there is also less probability of occurrence of leaf disease due to wetting, and this ultimately improves the biomass and water-use efficiency.
