Hydroponics is a type of hydroculture and is a way to grow various types of plants in water, without any soil, and with the addition of mineral nutrient solutions. All kinds of plants may be grown with their roots in the mineral nutrient solution only or in medium, such as perlite, gravel, or coconut husk. Usually, the soil acts as a mineral nutrient reservoir but the soil itself is not really necessary for plant growth. Plant roots can only absorb the mineral nutrients in the soil when the nutrients are dissolved in water. When the mineral nutrients are put into a plant’s water supply artificially, soil is no longer required for the plant to grow. Almost any plant will grow with hydroponics.