Important components of water management for transplant production include water quality, the frequency and volume of water application, and the method of application. Water quality factors of concern are alkalinity, soluble salts including sodium absorption ratio (SAR), and ions at potentially toxic concentrations including boron and fluoride. The available water in individual transplant cells is influence by container size and geometry, medium particle size, medium moisture release characteristics, and wetting agents but is primarily determined by irrigation frequency and the amount of water applied at each irrigation. Irrigation scheduling can be done using several methods but is influenced by the crop stage, the water volume applied, and the frequency of drying desired. Transplants can be watered by hose and breaker, stationary sprinklers, traveling boom sprinklers, fog nozzles, or subirrigation. The outcome of experiments testing effects of transplant size, transplant age and fertilizer rates are all influenced by water management.