Kratky Method Hydroponics
This simple method, first described by B.A. Kratky in 2009, is a relatively painless way to start growing hydroponically.
The mostly-passive technique involves suspending a plant in a net pot inserted into an opening in the top of a covered container filled with nutrient solution. The container can be as small as a plastic milk jug, or something larger like a 5-gallon bucket. 1-quart Mason jars are a popular choice.
Before placing the net-potted plant, the container is filled roughly 3/4 full, such that the root ends are touching the solution.
Over time, as the plant grows and uses some of the nutrient solution, the upper part of the longer roots becomes exposed to the moist air above the remaining nutrient. Thus, roots are both fed and oxygenated in the relatively closed environment.
As such, the method is nearly hands-off, other than making sure the root tips remain submerged.
Although lids and containers designed to employ the Kratky method are commercially available, resourceful gardeners have even been successful making homemade pots from disposable plastic cups and plastic foam rings to hold the plants.