The six most common types of hydroponic systems are:
1. Wick System
The wick system is one of the simplest forms of hydroponics. It utilizes a wick, which is usually a piece of yarn, cloth or rope, to transfer nutrient solutions from the reservoir up to the plant roots. One end sits directly in the nutrient reservoir while the other end passes through the growing medium to the root zone. The wick acts like a pipe, absorbing the solution at one end and transferring it to the roots at the other. As the plants use up the nutrients, the wick automatically draws more solution from the reservoir. Wick systems don’t require any power and provide a passive, low-maintenance way to grow plants hydroponically.
2. Deep Water Culture (DWC)
In deep water culture systems, plant roots grow directly into a reservoir filled with oxygenated nutrient solution. Air pumps continuously provide oxygenation through air stones in order to keep the solution moving and prevent stagnation. Since the roots have full exposure to the nutrient reservoir, it’s easy to monitor and maintain precise control over factors like pH, nutrient levels and temperature. The constant oxygen being pumped into the reservoir also allows for rapid growth. DWC systems are one of the most popular hydroponic methods among home growers due to their simplicity and effectiveness.
3. Ebb & Flow/Flood & Drain
Ebb and flow, also known as flood and drain, uses intermittent flooding of a grow tray containing the plants placed in a porous growing medium like clay pebbles or rockwool. At specific time intervals, a timer triggers a water pump to fill the grow tray with nutrient solution. Then the pump turns off, allowing the tray to drain completely before the next flood cycle. This provides the plant roots with nutrient solution, then oxygenates the roots once the tray drains. Grow mediums are well-suited for this method since they retain some moisture to keep roots hydrated between flood cycles. These systems are reliable, low maintenance and great for beginning hydroponic gardeners.
4. Drip System
In drip hydroponic systems, nutrient solution is delivered directly to the root zone by a network of tubes with emission points called drippers. Pumps or timers shut on and off the drippers to provide the plants with water on an on-demand basis. Since the plants can take up water at different rates based on environmental factors and genetics, close monitoring is required to assess the rate of water utilization. By observing the plants and adjusting the frequency of the drippers, growers can maintain optimal moisture levels in the root zone. Drip systems are adaptable, efficient and suitable for growing various plant types.
5. Nutrient Film Technique (NFT)
The nutrient film technique involves nutrient solution flowing through sloped channels in a thin film. Plant roots grow into these channels and are exposed to the flowing nutrient stream on one side and oxygen on the other. Since there is no medium, the roots hang in mid-air allowing full access to both nutrient solution and air. The constant flow of nutrient solution coupled with high oxygen content enables exceptionally fast growth rates. NFT systems require strict monitoring to avoid leaks and blocked channels, but provide superb growing conditions if properly maintained.
6. Aeroponics
Aeroponic systems offer the ultimate environment for hydroponic plant growth. Plant roots hang suspended in air under grow lights while nutrient solution is intermittently misted onto the exposed roots by a timer mechanism. This creates a highly oxygen-rich environment while also providing minerals, nutrients and water needed for growth. Since roots grow faster when exposed to more oxygen, plants often have accelerated growth rates with yields 20-50 percent higher than other soilless cultures. However, aeroponic systems require greater precision, investment and maintenance than other methods.
