People are always asking me, whats better to grow in, hydroponics or soil? I never have enough time when someone asks this question to give them a complete answer. The truth is it all depends on the growers skills and the situation, like are you growing inside or outside? All forms and methods of growing are essentially just different tools for the job. The art of growing plants without soil came from first understanding and using soil. Hydroponics is derived from the methods of growing plants in soil. You could call it a technological break thru or advancement in growing.
What’s best all depends on how you use each method and if you know how to use them properly. It also depends on the situation or location. One may not have much water around in his area, or may not have access to good organic soil, or the ability to get heavy bags of soil and the amount of water needed to the location of the garden. Hauling lots of heavy bags of soil up 3 stories to your apartment grow room is not very fun or efficient. Also, some plants seem to grow better and easier in either soil or hydroponics. To figure out which method is best suited for you to grow in you must first understand hydroponics and organics to make an educated decision.
Only 2 different dictionaries I found describe hydroponics as a science. The science of growing or the production of in nutrient rich solution (Websters New World College Dictionary, Fourth Edition, 1999), and the science of growing plants without soil (The World Book Encyclopedia, 1996). Most other dictionaries and encyclopedias define hydroponics as the cultivation, process or practice of growing plants without soil, all suggesting that hydroponics is a procedure of growing plants, not a science on how plants grow without soil. There are several variables and slightly different definitions of hydroponics so it really depends on how you define hydroponics. Most of us know or define hydroponics as the art of growing plants without soil
Lets look at some of the different types or methods of hydroponics systems and how they vary. Some of them include NFT (Nutrient Film Technique), Aeroponics, DWC (Deep Water Culture), Ebb & Flow, Fogging Mister Systems, and Drip Systems. Different hydroponic media are used within each system. Some of these media include hydroton grow rocks, rockwool, perlite, vermiculite, are inert and contain no natural nutrients or food. On the other hand some hydroponic media consist of coco coir, peat moss, mineral rocks, compost, bark, coco chips, and other ingredients that are organic, but consist of no soil.
NFT systems work well with lettuce, basil, and other green leaf herbs as long as you keep the water temperature under 68-70 degrees and your oxygen levels in the channels do not get too depleted.
Aeroponics works well on plants with smaller root systems because when the root systems get too big the sprayers or misters are not always getting at the root system evenly. The roots can block and even clog the sprayers and misters. Water temperature is critical here as well as is keeping the water quality clean and free of pathogens.
DWC systems are basically roots hanging from a net basket with a small amount of airy media such as hydroton grow rocks or perlite, not retaining much water. The roots grow out of the rocks and basket and down into the water or nutrient supply, which is also the reservoir in most cases. Air pumps supply oxygen to the nutrient solution where the roots are bathing and hanging. Problems here occur when the nutrient solution gets warmer than 70 degrees, and/or the oxygen supply is not high enough. Remember most pathogens and diseases develop best in standing water.
Ebb N Flow systems work by plants sitting in containers with well drained bottoms. A pump floods the table with an inch or two of water, a couple of times per day, and then it drain backs in to the reservoir. Some problems can occur here with pathogens and diseases when water conditions are not ideal.
Fogging or misting systems are very technical. Since it is literally a fog or fine mist spraying the roots everything has to be perfect. It is probably one of the hardest systems to grow with and learn to master, and requires the most maintenance and time. The roots can actually get too big to where they block the spray or mist from wetting the entire root system.
Drip systems are probably one of the easiest, most natural hydroponic systems you can grow with. It also allows the option for multiple different media to be used, but your watering cycles will vary with different media and systems. When you know how to use these systems properly and choose the right system for the right plants, just about anything can be grown in hydroponics.
To compare hydroponics to soil you must first understand soil. In hydroponics we are simply mimicking how plants grow in soil, so understanding soil growing will give great insight to growing hydroponically. Soil is a living micro-ecosystem that works totally different than hydroponic media. An example of an organic garden or ecosystem is the Amazon Rain Forest, a perfect microbial eco-system, organic and thriving. In soil, plants roots grow out wide and deep to search out and find nutrients and minerals. About 70% of a plants energy goes into root production and about 30% goes into foliage or fruit production. In hydroponics it is the exact opposite, with 30% energy going to the roots and 70% going to the foliage and fruit production. The roots spread out like an army of feeder roots absorbing the essential elements from the soil solution, which is in fact a very dilute solution. The soil is both mineral and organic in nature with many physical and complex properties.
Thru the process of solubilization and equilibrium chemistry, the elements removed by root absorption and up taken by the plant are replenished by this process naturally. In hydroponics you are giving a plant all the nutrients it needs so it does not have to work as hard to search for nutrients and elements, therefore having more energy to produce heavier, bigger fruits.
Normally one might judge the health of a plant by the size of its root system. A large mass of fibrous white roots would be considered the ideal situation for a healthy strong plant. That may not be the case in hydroponics. It has been demonstrated in studies that a single root is enough to supply a corn plant with phosphorous from early stage to maturity.
The larger root mass in hydro could be a negative in some situations. In the case of an NFT a plant, with a root system too large, it could actually clog up the drain lines and stop all water and oxygen from flowing down the channels to the other plants and they could die. On the other side, if minimal root mass is needed to supply the plants, a smaller root system would provide enough nutrients to the plant and allow for better oxygen levels in the nutrient solution and better flow of the solution in the channels. Smaller root systems in hydroponics could lead to better plant development, and heavier fruit set and size.
When using media such as coco coir, rockwool and hydroton the media develops complex properties similar to those in soil and creates soil like conditions, due to the accumulation of precipitates. When calcium and phosphates (whose surfaces absorb other elements such as copper, iron, manganese and zinc) build up in the media the precipitated elements accumulated are not removable by leaching. The EC levels can rise over time as well. All of this creates conditions similar to soil like properties in the media.
Since you are controlling what elements go into your nutrients, you can control what happens and what conditions grow and develop in the media and the plant. This is one of the benefits of hydroponics. Having ideal growing conditions and ideal nutrient solutions is what makes a perfect, healthy plant. In hydroponics you can adjust by adding or subtracting different minerals, nutrients or elements into the solution to make the plant grow a certain way, creating a perfectly balanced nutrient solution. You can also flush or clean out a plant much quicker than in soil which is a major benefit if you need to flush the plant out in case of a nutrient problem. Soil would hold the elements much longer than in hydro. The opposite is true in hydro in that the nutrient uptake by the plant is much faster and due to that comes the accelerated growth.
Almost 90% of the insects and diseases in your garden are soil born insects. By starting with a soilless hydroponic media you eliminate that 90%, and have a 90% less chance of having or getting bugs or diseases. Growing inside with hydroponics is cleaner, not as messy as soil and less work than to carry all of those bags of soil into the house. Can you imagine NASA taking tons of soil on the shuttle up to the space station to grow their produce for the astronauts? This could not be done in space without hydroponics. By controlling the nutrient solution and uptake to the plant one can fine tune their garden and plants. Plants can also grow up to 10 times faster in hydroponics. This does not mean you will harvest quicker or flowering will be faster. The vegetative growth is faster but the flowering time is the same genetically. It means you can trigger certain critical developments in the plant and fruit by adding or subtracting nutrients and other elements from the nutrient solution, and you have the ability to flush it within very short amount of time.
A couple other benefits of hydroponics are the fact that it uses about 1/10th the amount of water per plant compared to soil grown plants, especially in the field or in uncontrolled environments. 1 acre of hydroponics is equal to about 10 acres of soil grown crops, and with 80%-90% less water needed and much less labor, it is the better choice in many situations. As far as our Mother Earth is concerned, we’re loosing about 38 Billion metric tons of top soil per year due to several factors involving traditional field soil growing. Just the dust alone from the tractors tilling the fields takes away a lot of top soil in to the air, turning it in to dust. Mining, erosion, cutting down our forests and the many other harmful things being done to Mother Earth has all contributed to 38 billion tons of erosion annually. With hydroponics you are not watering into the ground pesticides or toxins due to the fact that hydroponics can be controlled, also not washing away our topsoil. Often times large hydroponic operations are small compared to field farms, are all recalculating systems, and have little to no waste in to the ground.
Are you sure you’re a dirt farmer? Most of us think we’re buying plants in soil from our nursery or Home Depot. The truth is most of these plants are grown in a soilless media such as perlite mixed with coco coir, peat moss, bark and other similar medias. They do this because of the plants ability with a smaller root mass to produce larger foliage and fruit growth. When you’re buying a plant this is usually what you’re looking at. The stores selling them do this, as it also saves them room and allows for more plants to be displayed for sale. Many of us think we’re growing in soil when actually there is no soil at all and it’s a good chance that it is a soilless hydroponics media.
There is no right or wrong answer to which is better, soil or hydro. There are benefits to each. You should first understand soil to better understand and grow successfully with hydroponics. The same results can be achieved in both systems, if done properly. There are more things to control and maintain in hydroponics to achieve the same success, but the same can be said for growing in soil. They are both tools and once you learn them and know them, you will find both easy to grow in. Many consider hydroponics a very valuable growing method that can achieve superior results without the use of heavy organic soils. As long as the growing conditions, environment, nutrient solution and everything else is ideal then anything will grow well in either media. But remember, one or the other may have benefits or advantages for your specific situation and growing needs.