OVERVIEW OF HYDROPONICS
Solving the labyrinth
When an individual first sets out on their indoor growing journey it can seem like a daunting task. Firstly, they may take a trip around their local hydroponics stores and get bombarded with a myriad of information about equipment, the best equipment, the best methodology, the best additives, the best prices and so on and so on. Their friends and associates also feed them information. “Use this, do this, no worries mate!” Often, this information seems contradictory – often it is! And let’s not even go there when it comes to forums (one question equals 20 different opinions etc).
So what gives? Which way to go? What are the tricks that give you maximum yields? Who do you listen to?
I can’t answer all of these questions. What I can give you is some simple advice that hopefully sets you on the right path. That is:
Science versus nature
Plants have been doing things very well on their own for thousands, tens of thousands, hundreds of thousands – millions of years. Certain plants grow well in certain environments, while others thrive in other types of environments. For instance, some plants like high levels of light while others thrive under significantly lower levels of light. Science has improved on nature somewhat – but then nature did pretty well on its own, long before science appeared on the scene. Science endeavored to understand the complex living organism that is the plant. By doing this, science was able to maximize the potential of plants by providing them with what nature had already achieved. Science simply enhanced this process, optimizing what nature had been providing all of the time. This is where it must all begin!
Kiss – keep it simple stupid
There seems to be an obsession with focusing on the stimulants, additives, new and improved formulas, maximum yields through some new discovery, some new snake oil – some new claim! The only problem with this obsession is that we often overlook the simple things – the elements that nature provides. These are: oxygen, carbon dioxide, light, water, nutrition, temperature, and air humidity.
While these elements play a complex role in how they affect plants and what processes take place because of them, there are some very simple rules. Additives and snake oils will do absolutely nothing when one or more of these factors is significantly out of whack. Get all of them right and you are 99.9% on the way to being a very successful indoor gardener.
The sum of it
Balanced macro and micro nutrition fed to plants at the correct pH, plenty of air that contains oxygen and carbon dioxide, desirable relative humidity levels, ideal ambient air temperatures, adequate levels of water and oxygen around the root zones of the plants, and quality light (intensity and colour spectrum) are the factors that promote growth.
Where hydroponics is concerned things differ only in that the plants are not grown in soil. However, the principles of hydroponics adhere strictly to nature’s rules.
The key to successful hydroponic gardening is understanding how a plant produces food and grows.
The manufacture of food for either a seedling or a cutting starts within the leaf structure of the plant. Chlorophyll, the substance that gives plants their green colour, converts carbon dioxide (CO2) from the air, water (containing nutrients), and light energy into carbohydrates and oxygen (O2).
This process is called Photosynthesis.
From this point on a complex process will determine the success or failure of your plant’s growth.
Hydroponics is the method or science in which you can supply all the essential elements to this complex system, along with natural sunlight and/or artificial lighting.
Plants are supported in a hydroponic system and nutrition is provided by water soluable, bio-available elements in conjunction with sunlight or an artificial light source. Because hydroponics provides the plant with well-balanced nutrition, hydroponic gardens can achieve amazing results!
Benefits of hydroponics:
- High bioavailability of essential mineral elements.
- Larger yields (see note below)
- Minimal wastage.
- High level of control over plant environment.
- More intense growing techniques requiring less space.
- Ease of manipulation of essential elements for maximum yield per square metre.
- Year round crop production.
- Growing can be facilitated almost anywhere.
- Less pesticide usage through biological pest control and through use of inlet air filtration
Comparison of Indoor Growing to Outdoor Growing re Yields
Studies of cannabis plants grown in the UK under outdoor conditions by the Laboratory of the Government Chemist have shown a range of dry weights (gross) per plant of 10.9 to 59.1g, 16 to 106g, and 8 to 80 g, with mean weights per plant of 30 to 60g. The variations in growth rates and THC content were ascribed largely to weather conditions. Other sources have stressed the variability of yields and the importance of environmental factors. Antother study evaluated plants grown outdoors and in greenhouses in Denmark finding median gross weights of 308g and 584g respectively, with a mean yield of 8.7% flowering tops after drying. GW Pharmaceuticals, who have a Home Office Licence to grow cannabis in the UK, report gross yields of 157g-188g m-2 in greenhouse conditions, 251g-397g m-2 indoors under mercury lights, and 516g-573g m-2 under HPS lighting (at between 10 and 17x plants per square metre). Actually, the latter number represents the picture well with a gram per watt being about the normal yield (genetics, of course, playing a significant role) achieved by indoor growers – 1.5 to 2 grams per watt also being possible with heavier yielding genetics. .