Drip irrigation is the controlled application of water at a very low flow over a prolonged period.
It differs from conventional watering systems in that the soil is not supersaturated with water. When the rate of drip irrigation is adjusted correctly, there are no puddles of water and no runoff. Some drip systems use small water-releasing mechanisms called emitters which drip a certain volume of water when a certain amount of water pressure is supplied. Many of these systems are prepackaged and allow little versatility or adaptation to various garden sizes and shapes. Several systems currently available in garden centers can be easily adapted to almost any garden size and situation.