Hydroponics is the new kid on the block when it comes to gardening. The name literally means “working water,” and the whole concept is that plants can be grown in a nutrient-rich solution without soil. This whole idea is actually not new at all but was born in the 17th century. Modern hydroponics didn’t come into its own until the last 100 years.
Root systems are supported in an inert medium such as perlite, rockwool, clay pellets, peat moss, or vermiculite. The basic concept is that the plant roots come into direct contact with the nutrient solution while also having access to oxygen so they don’t drown. The nutrient solution, which is basically a type of fertilizer, is determined by individual growers and can be either organic or non-organic.
Like most things, there are advantages and disadvantages to using hydroponics. The main argument for investing in this type of system is that plants have an increased rate of growth with increased yield. Plants mature 25% faster and produce 30% more crops than if they were grown in soil. Plants don’t have to work as hard to obtain nutrients so even small root systems will provide the plant what it needs. Thus, plants can put more emphasis on growing than on expanding its root systems.
All of this occurs because the nutrients and pH balance are critically monitored and controlled. Because systems are enclosed, less water is needed, which makes these systems ideal for areas where water is not plentiful.
With all of these advantages, the downside is that these systems are usually more costly than their soil counterparts, and they take longer to set up. Managing hydroponics requires a lot of time since nutrient levels and pH balances must be monitored daily.
Perhaps the greatest risk is a pump failure which can kill plants within hours of the malfunction, depending on the size of the system. Growing mediums can’t store water like soil can, so plants depend on a continuous fresh supply of water.
The term hydroponics encompasses several systems, with each one having its advantages and disadvantages. The bottom line with any of them is the method by which they supply water to plants.
Photo by Getty Images/Kapook2981.
The easiest type to manage is the deepwater culture, also known as the reservoir method. Roots are suspended directly in the nutrient solution and an aquarium air pump oxygenates the solution. Light must be monitored because too much will let algae grow. The benefit to this system is there are no spray emitters to clog, especially if using an organic solution, since that is more prone to clogging.
The nutrient film technique involves a continuous flow of the nutrient solution over the plant roots. This system is powered by gravity with the plant bed being on a slight tilt. With this method, only the plant roots come into contact with the solution, enabling the plants to get more oxygen, which means a faster rate of growth.
With aeroponics, the roots are misted with the nutrient solution while they are suspended in air. This is achieved by using either a fine spray nozzle for misting or a pond fogger. The AeroGarden is a commercialized aeroponics system which is an excellent entry point to aeroponics. It is a turn-key system that requires little setup and features great support and supplies to start.
Wicking is one of the easiest and lowest cost methods of hydroponics. The concept here is to have a material such as cotton that is surrounded by the medium with one end of the wick material placed in the nutrient solution which is wicked to the roots of the plants. This method can be simplified further by removing the wicking material altogether and using a growing medium that can wick the nutrients directly to the roots.
Ebb and flow is yet another method, also known as flood and drain. The idea here is to flood the growing area with the solution at specific intervals and then let the solution drain back to a reservoir. A pump hooked to a timer ensures that the process repeats regularly. This system is ideal for plants that flourish when they go through a slight dry spell because it encourages the root system to grow larger in search of moisture. As they do this, the plants grow faster because they absorb more nutrients.
The drip system is rather simple. It involves a slow feed of solution to the plant medium. In these cases, the medium must be slow-draining such as rockwool or peat moss. Faster draining ones may be used, but a faster dripping emitter must then also be used. The downside to this technique is that the drippers clog frequently.
No matter which method you choose, there are some tips for success that are relative to all. First, change the nutrient solution every two to three weeks and keep the water temperature between 65 and 75 degrees F. Using an air pump can increase the circulation and keep the nutrient solution oxygenated. Remember too, that plants still need 4 to 6 hours of direct sunlight per day.
Flush, clean, and sterilize the system after each growing cycle. Drain the reservoir and flush with a mixture of 1/8 cup non-chlorine bleach to one gallon of water. Run this for a day and follow-up with clean water. At any time during a growing cycle, if the plants do not look healthy, check the pH balance, and if it is off, then flush the system at that point also.
Hydroponics is an excellent growing choice for all types of plants because growers can meticulously control the variables that effect how plants will grow. A fine-tuned hydroponic system can easily surpass a soil-based one when it comes to plant quality and amount of yield.
On the flip side, taste is often a casualty of the hydroponic system. Though all the nutrients that plants receive can be controlled, there is just something about growing them in soil. Every soil is different, and each type can add its own “flavor” to produce. Hydroponic growers can regulate plants’ sugar, sodium and acidic flavor by what is added to the growing solution.
So, should you ditch your regular garden in favor of hydroponics? It's just my personal opinion, but there is nothing that will replace good old dirt. Hydroponics does offer a way of growing more food for feeding all of us, but it is offered at a price, which is taste. It would be fun to experiment with these systems, but I’m not ready to give up my dirt just yet.