Aeroponics is a soilless plant growing method where bare roots are periodically sprayed with a nutrient solution. It is considered more advanced than hydroponics as it allows for unlimited oxygen and nutrient supply to plant roots. In aeroponics, roots are exposed to nutrient-rich mist rather than being submerged. True aeroponics uses no growth medium, but hybrid methods that employ sprayers and some growth media provide benefits of both aeroponics and hydroponics. The earliest aeroponics patents date back to the 1950s and 1960s.