Soil or Soilless -- The case for hydroponics

I'm often asked a "Which is better, hydroponics or soil?" Each method has their advantages and disadvantages that require certain personality traits to maintain and to be successful with. If you stick a plant in soil, it grows in what plants are genetically engineered to grow in, earth, or in many cases a custom mix of earth concocted by one of our friends at a potting soil company. Planting mixes are often charged with nitrogen and phosphorus in the form of earthworm castings and bone meal, which assist the plant with a much-needed boost to handle its vigorous root and vegetative production. The soil acts as the plant's foundation and food source while providing a cool, moist environment for a plant to stretch out in and search out life giving nutrients.

With hydroponics, the gardener needs to provide the plant with everything it needs to survive. The medium used in hydroponics should have a good air to water ratio. Potting soil is not suited for hydroponics applications because of its absorption. After a thorough watering, soil may remain soaked for days. Most hydroponics systems require a pump of some kind set on a timer that waters at the very least once a day, most of the time. If you saturate soil once a day, your plants will last about a week before they suffocate and drown, especially when they are young. For example, If you had an ebb and flow garden (I will explain the strange but alluring term "ebb and flow" soon enough), and your plants are growing in a rock medium of some kind, you would set the pump on a timer to water four or more times a day. The plant will feed out of the nutrient solution and spend the next four hours or so until the next watering soaking up the traces of nutrient on the rock medium and taking in oxygen through its roots. More waterings mean accelerated growth, one true advantage to hydroponics. Some preferred materials used as mediums are expanded clay pellets, perlite (a white, brittle, processed volcanic rock often used as a soil amendment), rockwool (rock that has been melted and spun like cotton candy, resembles fiberglass), coco coir (shredded coconut husk), and sand. In soil, a plant's root system needs to move through the soil to retrieve nutrients. In hydro, a gardener is essentially sticking a feeding tube into the plants system and pumping it with exactly what it needs, so the plant spends less time on making roots and more time growing on the topside. This is where your personality comes into play. A plant growing in soil has something to go off of, that being the soil itself. Fertilizing is not necessary in the first couple weeks if needed at all due to the fact that the soil is the food, so the gardener merely needs to water. That's not a luxury in hydroponics. The medium in hydroponics comes with nothing, nada, zilch. No nutrients in any shape or form (there are always exceptions to the rules, so read the bag!). You feed the plant everything it needs for survival, so that means hydroponics is not as forgiving as soil when it comes to mistakes. If you exceed the recommended amounts of fertilizer in soil, you have a few days to catch the problem and flush the excess fertilizer away from the roots to correct the problem. If you do this in a hydro system, your plants could fall on the floor in a matter of hours! Now don't let this scare you away. Hydroponics is really is not as complicated as everyone makes it out to be. All you need to be concerned with is PH and PPM. There are digital pens and meters on the market you can get for under a hundred dollars that will considerably make your life easier. The meter will indicate with an easy to read digital readout how concentrate your nutrient solution is. PPM means Parts Per Million. Almost everything you feed your plants are metals - calcium, magnesium, iron, and manganese to name a few. The PPM meter simply divides the solution into a million parts of water, and tells you out of those million parts of water how many parts of the water is something else. PH is just as important as PPM. The availability of metals is governed by PH. That means wrong PH, no food for the plants.

Another important choice is what kind of food to use. There are many different hydroponic solutions out there you can use, that usually come in three or more parts. The reason for dividing nutrient components into different parts is not only make these nutrient companies a lot of money, but it is also to make the nutrients shelf stable and avoid lock-out. Nutrient lock-out occurs when certain metals in its concentrated form will attract each other and bond forming a molecule that is too large for the roots even to ingest, rendering your nutrient solution worthless. At that point you might as well be giving your plants plain water. When lockout occurs you will quickly see your plants suffer in the form of drooping leaves, red stems, and purple veins on the leaves, truly a sad sight. Lockout is not exclusive to hydro; it is just as common in soil. If you fertilize with every watering, like most nutrient manufactures want you to do, chances are you will experience a lockout sometime throughout your growing cycle. That is due to the fact that in soil, unlike hydro, you have no idea what the soil is holding on to and what the plant has used. There is no practical soil meter that will tell you accurately exactly what's going on in soil. If you experience a lockout and your plants are suffering, flush the growing medium to leach (or rinse) access fertilizer away from the root mass. In soil this can be a daunting task because that requires every container to be flushed with gallons of fresh water. In hydro the flushing process is a snap, just drain and discard tainted solution in the reservoir and replace it with a new batch. Another point for hydro!

If you haven't caught on by now, I'm a hydro guy. Hydro is clean, easy, fast, and in my opinion better. Now I've been accused of going to the dark side, of being a "Chem Guy", referring to non-organic compounds in the form of red and green chemical fertilizers that have been used as hydro food for years. My friends, things are drastically changing! We are now experiencing the dawn of hydro. Countless numbers of organic nutrients and additives are popping up everywhere. Once, emulsification and chelating were achieved with chemicals. Now organic compounds cultured with beneficial bacterial inoculations are replacing chems.

We have yet to scratch the surface on what is possible in the realm of hydroponics. The purpose of this column is to explore all of them. Don't be afraid. Don't fight the movement. Give in and let's learn together, for there are hundreds of ways to grow, and unfortunately I'm facing a word count restriction, so until next time. Love your plants and they will love you.

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