All are methods of growing plants, but how do they differ?  Geoponics refers to traditional gardening, planting in soil. Hydroponics and Aeroponics are unique in that no soil is used at all! This is what makes them ideal for an indoor, or outdoor, garden at home.
Lets start with growing media. The substance in which a plant is grown, is known as the growing medium, it supports, moistens and/or feeds the root structure of a plant. Soil is one example of a growing medium. Hydroponics uses water as its growing medium, and Aeroponics grows plants, literally, in air. The latter two Use liquid based nutrients which are mixed with water, known as Nutrient solution or hydroponic nutrients. 
If you’ve never heard these terms before, don’t worry, that not unusual. Hydroponics is simple if you know what you’re doing, and that is why your here.

 

There are six main types of hydroponic systems, including aeroponics, but there are countless variations which are possible from them. (For more detail on each of these read the page 'Hydroponic Systems')

It is usual in Hydroponics to use an ‘inert medium', meaning it is something that doesn’t contain nutrients. This could be gravel or small clay balls which the roots can grow around for support. Having this 'inert' medium means that you can absolutely monitor how much nutrients you are giving your plants. These nutrients are purchased in highly concentrated liquid form, are diluted in water, and are either circulated through pipes into which roots hang, or is introduced to the roots in some other way depending on the type of system.

 
Growing plants without soil may sound unnatural, but hydroponics can be completely organic, it all depends on which nutrients YOU decide to feed your plants. Compost tea, if you have a compost bin, will be loved by any plant.  In fact, it is also a very eco friendly way to grow, in most cases conserving 70% more water than conventional geoponics. This is because the water is continuously cycled to the plant roots, instead of mostly draining away.

 

 

Plant roots need water, nutrients and darkness, as well as oxygen. In Aeroponics, a plants roots are suspended in a ‘root chamber’, hanging in thin air. Air, in fact, is the growing medium in this techneque. To keep them fed and prevent from drying (a fatal matter for roots), nutrient solution is sprayed as a mist, into the root chamber. This occurs periodically every few minutes. Aeroponics can be applied to indoors as easily as hydroponics. 

Like hydroponics, Aeroponics has immense economical benefits, saving more water and nutrients even than a hydrponic setup. One drawback to this techneque is the sensitivity of the roots, should a pump or timer stop working plant roots will beging drying quickly. Nonetheless these methods are so efficient that many large scale farming operations already exist. Also, as far as plants go, virtually anything can be grown with Hydroponics and Aeroponics.