The banks were to defend the crops from flood. Wadi Yenbo otherwise would soon have filled the gardens, since these, to be irrigable, must be below the valley floor. The narrow plots were divided by fences of palm-ribs or by mud walls, with narrow streams of sweet water in raised channels round them. Each garden gate was over water, with a bridge of three or four parallel palm-logs built up to it for the passage of donkeys or camels. Each plot had a mud sluice, scooped away when its turn for watering came. The palms, regularly planted in ordered lines and well cared for, were the main crop; but between them were grown barley, radishes, marrows, cucumbers, tobacco and henna. Villages higher up Wadi Yenbo were cool enough to grow grapes.