Hydroponic Gardening Guide: 5 Types of Hydroponic Systems

Hydroponic gardening is a method for growing plants without soil. Plants grown hydroponically do not sit in soil but rather in a growing medium that transfers water and a nutrient solution to the plant roots. Most hydroponics systems are housed indoors, where the grower can control all elements of the plants’ life cycles.

An indoor hydroponic garden typically contains the following:

1. 1. Grow tray: The grow tray is simply a container that houses the plants.
2. 2. Growing medium: The growing medium fills the role that soil plays in a typical garden. It anchors the plant's root system and transfers nutrients to those roots. This soil subsitute can be made out of vermiculite, mineral wool, coconut fiber (known as coconut coir), peat moss, clay pellets, sand, perlite, and other such materials.
3. 3. Reservoir: Typically located beneath the grow tray, a reservoir holds water and dissolved nitrogen-based nutrient solutions. These liquid nutrients transfer from the reservoir to the plants via an ebb and flow hydroponics system, which controls how much water is delivered to the roots.
4. 4. Water pump: A submersible pump located in the reservoir powers the hydroponic nutrient flow system.
5. 5. Air pump: In addition to water and soluble nutrients, growing plants absorb carbon dioxide (and give off oxygen). An air pump ensures that there is enough carbon dioxide within the hydroponic gardening system.
6. 6. Grow lights: Indoor gardening requires the same warmth and ultraviolet light that outdoor plants get from the sun. Grow lights, or sun lights, provide this to your indoor soilless plants.

For many vegetables and houseplants, hydroponic gardening offers notable advantages over traditional outdoor gardening.

1. 1. Reduced water use: Although hydroponic grow systems use a reservoir full of water, the recirculating nature of these systems results in less water use overall. Runoff is captured in drip systems that return the water to the reservoir for future use.
2. 2. Efficient use of space: Home growers and professional farmers don't always have access to all the land they need. Whether you're an apartment dweller looking to grow your own tomatoes or a commercial farmer seeking to grow more kale or chard for the farmer's market, hydroponic systems can help you do more with less. Scientists have even made hydroponics work in the confines of the International Space Station.
3. 3. No weeds: In outdoor gardens, small plants can be overwhelmed by weeds. Hydroponics eliminates the possibility of weeds, thus preserving valuable nutrients for your crops.
4. 4. Faster growth rate: For certain species like tomatoes and leafy greens, hydroponic systems allow plants to grow faster than they would in the ground. This rapid plant growth can accelerate the crop production cycle and get produce to market faster than traditional methods allow.

Growing plants in a hydroponic garden can be fairly simple once your system is set up, but choosing the right system can be tricky. There are several popular types of hydroponic systems, each with their own pros and cons.

1. 1. Wick system: This type of hydroponic system tends to be easiest for beginners. A grow tray sits above a water reservoir containing a dissolved nutrient solution. Various strands of wick connect the reservoir to the growing medium, transferring nutrients to the plants’ roots.
2. 2. Nutrient film technique: In the nutrient film technique (NFT), no growing medium is required. Instead, nutrient solutions pump continuously onto the grow tray, which is slanted to drain back into the reservoir. Plant roots absorb nutrients as they flow beneath them. The downside to NFT is that it requires a continuous source of electricity to keep the water flowing.
3. 3. Deepwater culture: This hydroponic system, often abbreviated as DWC, works for plants whose roots can stay submerged in water at all times. The plants hang in net pots above a reservoir, and the roots reach down into the water. Aeration occurs with the help of an air stone, which sits in the water and promotes the release of oxygen and carbon dioxide.
4. 4. Aeroponics: In some ways, aeroponics is the opposite of deep water culture. This grow system hangs plants high above a water reservoir with their roots exposed to the air. A nutrient water pump sprays the roots at regular intervals to keep them moist. Like NFT, this grow system does not require a growing medium, and it also requires a continuous source of energy to power the pump.
5. 5. Drip hydroponics: A drip system is perhaps the hydroponic technique that most resembles soil-based gardening. Plants sit in a growing medium in grow trays. A nutrient pump sends water to a drip manifold, which distributes the nutrient-rich water to individual drip lines. Each of these drip lines deposits water on the growing plants.

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