The experiment, designed to investigate the production of alfalfa in Saudi Arabia, was a factorial involving three irrigation rates and three cutting heights. The irrigation rates were sub-optimum, optimum and super-optimum, supplying 2730, 3850, and 5040 mm of water over the duration of the experiment respectively; cutting heights were low (2 cm), high (8 cm) and alternate (2 cm and 8 cm). The experiment ran for a year, with 14 harvests. Sub-optimum, optimum and super-optimum irrigation treatments produced 27·5, 31·4 and 31·9 tonnes of DM per hectare respectively. Proximate analysis of crude fibre, crude protein, and ash percentage were determined, and plant density and weed infestation recorded.