Overview of Hydroponic Cultivation Methods Hydroponics is the science of nurturing crops without the use of soil, where the cultivated crops are supplied with nutrients through a fluid media. More often, hydroponic cultivation methods rely on water alone as the dominant medium through nutrients are supplied to the crops. According to Nicholls (1999, p.7), the benefit of hydroponics is that, it requires small space to grow large number of crops. In addition, the system of growing crops using hydroponic methods facilitates faster growth of crops, and hence higher yields within a very short period. More so, arid and semi-arid areas can sustain crops using this cultivation method; since the plants usually grow faster and make good ground cover to reduce evaporation (Patten 2004, p.19). This paper will discuss various methods of cultivating crops using hydroponics system. Commonly Used Hydroponic Cultivation Methods Nutrient Film Technique (NFT) The Nutrient Film Technique, also called water culture hydroponics, is one of the most productive methods of hydroponics used for growing commercial crops. In this method, crop roots are grown in light-tight and shallow channels that are supplied with nutrient in water circuits. The nutrients are dissolved in water, where the solution is continuously allowed to circulate within the rooting system of the crops for about 20-24 hours per day. According to Keith (2003, p.23), the film of water flowing in the roots of the plant should be made as shallow as possible to facilitate efficient flow of oxygen within the rooting system of the crops as much as possible. One main advantage of Nutrient Film Technique is that, it facilitates the growing of numerous crops in a very small space, thus most useful in space-limited areas like towns (Nicholls 1999, p.44). It is also important to note that, this method does is not labor intensive since it requires no weeding or manual watering of the crops; since the nutrient solution is made to circulate automatically within the growing channels. This method is also advantageous in the sense that, it can support a wide range of crop varieties. Aggregate Culture Hydroponics Aggregate culture hydroponics is also called passive sub-irrigation. This is a technique of growing crops in sand or gravel, where water mixed with nutrients is pumped in the gravel tank where the crops are planted in. One advantage of this method is that, the plants are not necessarily held in water film, since they can acquire anchor from the gravel or sand in the container (Howard 2003, p.26). Once the tank is filled up with water mixed with nutrients, the water can easily be drained away after the roots get moistened and absorb enough nutrients. The water drainage in this case can be drained up after 5-8 hours of flooding. By pumping or draining the water in the rooting system, aeration in the rooting region of the crops is facilitated, making the crops grow healthy (Patten 2004, p.95). According to Keith (2003, p.37), passive sub-irrigation involves the transportation of water and nutrients using capillary action. As a result, it is considered as one of the best methods of hydroponics since there is minimum utilization of labor. Since the rooting system of the plants is highly aerated, root rotting is least experienced using this method as compared to other methods. Further, the supplementary ambient