Generally experts classify hydroponic plant growth system into six categories.
- Wick System
- Ebb and Flow / Flood and Drain
- Deep Water Culture (DWC)
- Nutrient Film Technique (NFT)
- Drip Systems
In this article, we will discuss four systems out of these that can easily be set up in homes and gardens.
Wick system is the most basic and probably the oldest hydroponic technique that has been used for centuries. This technique works passively and doesn’t require any water or air pumps. The mixture of mineral nutrients and water is transported to the roots through wicks. The wick can be easily made by a piece of felt or rope.
A growing medium that can facilitate the movement of water and nutrients to the plant roots can ensure a successful wick hydroponic system. Vermiculite and coconut coir are good choices for this.
The wick hydroponic system is great for beginners. However, it is not perfect and there are some limitations which should be mentioned.
- It is not suitable for growing plants that need large amounts of water and nutrients
- Even the slightest misplacement of the wick can spoil the whole system
Ebb and Flow / Flood and Drain Systems
In ebb and flow or flood and drain system, the roots of the plants are not exposed to the mixture of water and solution constantly. Instead, the tray which contains plants and growing medium is flooded with the nutrient solution a few times a day. The flooded solution is then drained down to the reservoir via gravity which is used again for flooding with the help of a water pump.
This hydroponic system uses water and energy efficiently. However, it uses a lot of growing medium and you have to be very careful with the duration of the nutrient flood, otherwise you will be end up with dead plants.
Deep Water Culture System
Deep water culture (DWC) hydroponic system is used widely these days for hydroponic growing. This system comprises of a reservoir containing the nutrient solution in which the plant roots are dipped constantly.
To oxygenate the water, and consequently the plant roots, an air pump is also used in the reservoir. Plants are usually placed in foam media that is fixed on the top of the reservoir.
DWC systems are great for growing small plants and can be made and maintained at a very low cost.
Nutrient film technique (NFT)
It is a popular hydroponic technique that is used to grow plants with smaller roots. A channel is used and pumped with nutrient solution which runs as a thin layer at the bottom of the channel. Due to the thinness of the nutrient flow, this technique is referred as nutrient film technique. The channel is slightly inclined so that the nutrient solution, once it passes through the roots, can go back into the reservoir.
NFT needs minimal growing medium and produces less waste since it’s a re-circulating hydroponic system. The technique is suitable for growing leafy vegetables because they have shallow roots.
Drip system is mostly used for commercial purposes while aeroponic system constitutes of complex structure. Therefore, these two techniques are not usually used for home-based hydroponic growing.