Soil. Water. Say that plants don't need them and people may think you've traded your cow -- and your good sense -- for a handful of beans. But NASA-sponsored plant experiments prove that you don't need soil and lots of water to grow a beanstalk that would make Jack proud.
Aeroponic growing systems provide clean, efficient, and rapid food production. Crops can be planted and harvested in the system year round without interruption, and without contamination from soil, pesticides, and residue. Since the growing environment is clean and sterile, it greatly reduces the chances of spreading plant disease and infection commonly found in soil and other growing media. [NASA]