Hydroponic gardening raises a big question, is soil necessary? The Hanging Gardens of Babylon made quite a name for themselves by utilizing hydroponics. Anyways, most plant lovers look primarily to plants for growth, low effort, and/or a pleasing aesthetic. Soil can increase this effort and it is common to overlook the importance of soil, and managing the pH of soil, to produce great results for plant growth. So why not take soil out of the equation?
Soil provides two main purposes in the natural environment: one, to protect the plant from erosion and other hazards, and two, to hold nutrients for plants to grow. If you’re growing plants indoors or in a controlled environment, a hydroponic system is a fantastic choice to increase your plant growth and be more efficient with water and energy.
What is Hydroponics?
Hydroponics is soilless gardening. Hydroponic systems take soil out of the equation and allow plants to grow by suspension in or around a nutrient water solution. Since the nutrients and hazards are taken out of the plant’s life, soil is not necessary and a hydroponic system can be utilized for efficient plant growth. Imagine floating water plants but this same setup can be achieved for plants that cannot naturally grow in aquatic environments. The plant roots will then freely absorb nutrients from the water solution and grow, considering sunlight, space, and other growing conditions are already checked off on the list.
Many home remedies and industrial offshoots of hydroponics exist for growing plants. Customizability is highly achievable with hydroponics, even more so if adequate monitoring equipment is available for temperature and oxygen (to name only a few). In this way, hydroponics can tailor to all plant varieties for optimal growing conditions and results. You may have even seen a setup at your local greenhouse. Nevertheless, all the hydroponic systems that exist funnel down into six main types of hydroponics.
Ebb and Flow
NFT (Nutrient Fluid Technique)
This article will help you understand and choose the correct hydroponic setup for your situation. In fact, according to Green Our Planet, hydroponic systems can grow plants up to twice as fast, yield three to ten times the amount of growth in the same space, and save up to 90% more water than traditional soil gardening. This is all on top of the increased control a gardener has with a hydroponic setup over oxygen, humidity, temperature, pH monitoring, lighting, etc. If you aren’t convinced of this futuristic gardening technique just yet, let’s explore the 6 different hydroponic systems that you can build.
Basic Hydroponic Systems
In short, aeroponic systems utilize an in-air suspension and misting devices to spray the plant roots. The excess water will then drip off the roots into a reservoir below to be recycled back through the misting nozzles. Very water efficient. All types of plants can be grown in the aeroponic system as long as the reservoir dimensions are big enough to house the size of plant you intend to grow, which is a large advantage of this approach.
The downside to this system is that it can be increasingly difficult to set up compared to other hydroponic systems and is probably the most advanced of them all. Since the roots are suspended in air the misting intervals need to be relatively short, requiring a short cycle timer and increased energy consumption to prevent plant dry out. Due to the high number of mistings, these nozzles can clog up over time and become difficult to clean due to the nutrients and impurities in the water itself. Likewise, humidity is a concern with this setup to avoid plants drying out if the system fails; this issue can be easily monitored and prevented with a humidity sensor. Overall, aeroponics is an extremely efficient approach to hydro farming if the time and resources are available to set up and maintain the system.
Compared to the most advanced hydroponic system, the wick setup is probably the easiest approach of all the hydroponic systems. It requires no electricity, fancy pumps, or misting devices. The basic idea is like an old, oil wick candle. The wick (usually nylon) is submerged in a water nutrient solution reservoir and then fed up into the growing tray of plants—which holds an absorptive substance like vermiculite or coconut fiber to transfer nutrients from the wick to the plants.
This approach is very useful for simple setups and small scale gardening like house herbs. It requires little effort after setup, but is not a favorable option for large plants and plants which require a lot of water like tomatoes. The simple wick approach also decreases the uniformity of nutrient distribution to the plants. Proper checks every few weeks are recommended to maintain proper nutrient levels; this can be easily achieved using a conductivity probe to check the EC levels of the water. Preventative maintenance will also reduce nutrient buildup from excess particulate in the reservoir solution which can interfere with the wick nutrient transfer.
Water Culture Hydroponic Systems
Staying in the simplicity realm, water culture hydroponics also offers a very easy approach to hydro gardening. All you need is some sort of water reservoir, a net pot, and nutrients. This setup is very customizable for different plant sizes without having to alter many other inputs. Simply set up the correct size net pot, reservoir, and submerge the plant into the nutrient solution. Small scale water culture setups can even be made in a mason jar, whereas deep water culture for large plants is also a possibility.
Water culture hydroponic systems have a huge advantage over the wick setup by allowing plants to constantly suck up nutrients as the roots are always in contact with water. However, if not properly managed the roots can develop diseases, rot, and die. In this way proper nutrient levels, pH management, and dissolved oxygen monitoring of water culture setups are very important to prevent dirty growing conditions for the plants. The use of an airstone or pump to oxygenate the water is highly recommended. Overall, water culture hydroponic systems can provide a very simple and intuitive method for increasing plant growth rapidly.
Ebb and Flow Hydroponic Systems
Ebb and flow hydroponic systems allow the nutrient solution to flood and drain from the plant grow bed via a submersible pump. This system utilizes an ocean tide like “ebb and flow” to soak the plant roots in their growing bed of an absorptive medium, but minimize the chance of plants being oversaturated with moisture. The pump will have cycle times to stop and start the flooding of the grow bed, giving time for the water to drain into a reservoir (typically below the grow bed).
This growing approach requires more space than the other approaches discussed and therefore reduces the likelihood of using large plants due to space demands. It also requires a bit more engineering by introducing a submersible pump, but lends itself to higher customizability based on your plant needs. To increase the technicality even further, flow meters can be used to fine tune the ebb and flow cycle for the most optimal growing conditions. Be careful of overflowing the grow bed! If done properly, the automation and self-driving setup is truly something to be proud of all while producing impressive growing results.
Hydroponic Drip Systems
Speaking of customizability, if you frequently change your plants and/or gardening approach, the drip method will be in your best interest. This method drips water onto the plant roots which are usually planted in an absorptive growing medium. The excess water that drains into a reservoir will be pumped back up to restart the cycle. This approach is similar to the aeroponic misting cycle and can use similar oxygen gas monitoring, although it is less advanced by using different tube variations for the drip instead of misting nozzles.
Simple setups can be performed by manually refilling the dripper tank from the drain reservoir, or you can set up two pumps (one to mix and oxygenate the solution, and one to move the solution from the reservoir up to the dripping nozzles). It is recommended to use the pump approach for a self-driving process unless you are experimenting on a small scale with this hydroponic system. Overall, the drip system is very flexible to the available space, type, amount, and size of plants that you wish to grow, but can become cumbersome with maintenance and upkeep of multiple pumps and reservoirs.
Nutrient film technique for hydroponics
The nutrient film technique in a way combines the drip, ebb and flow hydroponic systems in a more advanced setup. The basic idea is the same: a growing bed and reservoir beneath it for nutrient drainage. The growing bed is usually tilted in one direction to allow this solution to drain, creating just a thin layer of nutrient solution that the plants will absorb from as it passes by (hence the “film” title). Due to this thin layer, smaller root plants will work best with this technique but the NFT setup can scale up or down relatively easily depending on your circumstances. Also, it is advised to use net pots versus an absorptive growing medium to allow enough nutrients to reach the plant roots.
This NFT hydroponic system becomes more complicated due to multiple pumps for oxygenation and pumping the reservoir solution to the growing bed for a continuous cycle. Additionally, if anything malfunctions the plants can dry out very quickly due the stoppage of thin water flow to their roots. That being said, all the growing inputs can be highly monitored with this approach and will yield some of the highest hydroponic system growing results—making it widely accepted in the hydroponic world.
Aquaponics Versus Hydroponics
Aquaponic systems use a similar approach to the water culture system but instead of adding nutrients one would add live fish. This method is usually used to combine fish and plant farming into one closed system. The idea behind the fish is that they will produce waste, which then turns into nutrients for plants (i.e. nitrates and ammonia). Ideally the fish live happily, the plants will clean the water, and all parties flourish; however, the balance can be tricky due to the potential of dirty water killing the fish or not enough fish waste to feed the plants.
This approach is not necessary if you’re primarily concerned with growing plants but deserves an honorable mention in the hydroponic system discussion, as aquaponics is a form of hydroponics but not all hydroponics are aquaponics (a common misconception).
What is the best hydroponic setup for me?
The first thing to consider is how much time and effort you want to expel into a hydroponic system. Low effort setup and maintenance hydroponic systems would align more with the wick and water culture systems, whereas the drip, ebb and flow, NFT approaches will require more engineering to setup and maintain. Maintenance requirements per hydroponic system vary slightly but they all boil down to similar parameters, which can be easily monitored with Atlas’s wi-fi hydroponics kit. This device will provide real time measurements for pH, conductivity, and temperature to ensure the hydroponic system has optimal conditions.
The same idea goes for the size and scale of your plant production. One must consider the space available. For example, in a water culture system it would not be advisable for large scale growing operations because large scale operations become more costly. Also the type and variety of plants you’d like to grow will be a large factor in choosing a hydroponic system. The drip and ebb and flow techniques will provide more customizability and flexibility for a higher variety of plants but will require more setup.
To summarize, the pros and cons of all six hydroponic systems are listed below.
Pros & Cons
Pros: Highly water efficient, no growing medium to consider, plants are highly oxygenated 24/7 Cons: More expensive and difficult to setup/maintain, small wiggle room for error
Pros: Simple. Inexpensive. No pumps or electricity Cons: Large plants will not receive enough nutrients, inconsistent nutrient distribution
Pros: Simple. Inexpensive. Easily customized and supports wide variety of plant types Cons: Can be cumbersome on a large scale. Plants more susceptible to rotting if dissolved oxygen isn’t monitored correctly.
Ebb and Flow
Pros: Customizable, lower energy requirement of the automated setups Cons: More difficult to setup, requires more space
Pros: Flexible for any space and variety of plants Cons: Difficult setup and maintenance for automated process
pH probes contain two electrodes (a sensor electrode and a reference electrode) that measure the hydrogen-ion activity in a solution. The exchange of ions generates a voltage that is measured by the pH meter converting the voltage into a readable pH value. The glass electrode was invented by Nobel Prize winner Fritz Haber in 1909,
Temperature sensors are a device used in our everyday lives to measure the temperature of the air, a liquid, and solid matter in a wide range of industries and applications. Temperature sensors are found everywhere. If you have ever received a notification on a hot day that your smartphone has got too hot, that is