To provide a water sprinkling method and a watering system in a cell-form seedling-growing unit that can grow seedlings of high quality with little dispersion at a low price.

The culture medium 12 is arranged in a cell 10 having the water sprinkling hole 11 bored at the lower face and seedlings 13 are planted to the culture medium 12 and water is sprinkled to the seedling. A nozzle 21 is inserted from the lower face of the cell 10 through the hole 11 into the culture medium and the nutritious liquid 31 is injected into the medium. The insertion height of the nozzle is set to multiple steps and the nutritious liquid 31 is injected dividedly at the individual insertion heights and the insertion height of the nozzle and the amount of nutritious liquid 31 to be injected is computer- controlled.