5 Minute Quick Intro

Indoor vs Outdoor Growing

Advantages Although artificial light has disadvantages to outdoor growing, we can use it to our advantage as we have full control on the intensity, amount and period of light.
We now have full control of the season from anywhere in the world. That means we can grow almost anything (but not tall plants). OK, almost anything.

Disadvantages The disadvantage of growing indoors vs outdoors is the need of artificial light. The biggest drawback is that artificial light is dependent on distant of light source to plant. The lights need to be kept very close to be effective. Knowing this we tend to grow shorter plants and aim for the SOG (Sea Of Green) method, a horizontal plane of green.
Another disadvantage of using artificial light is of course the running costs.

Lighting We generally use 2 types of electrical lighting:

1) HID (High Intensity Discharge) Lighting  These types of lamps produce light by means of an electrical arc between tungsten electrodes inside an arc tube. The tube is filled with both gas and metal salts. The gas facilitates the arc's initial strike. Once the arc has started, it heats up and evaporates the metal salts forming a plasma, which massively increases the intensity of light produced by the arc. The types of gas used in the arc tubes are of 2 types used in growing:

• Metal Halide:  Produces a lot of blue light, which simulates the middle of summer months. This greatly increases the vegetative stages of growth.
• HPS (High Pressure Sodium):  Produces a lot of red light, which simulates the end of summer months. This is used for flowering and fruiting stages of growth.

HID lamps require a ballast (control gear) which is a box of tricks to control the voltages required to initially start the arc and then control the voltage once the arc is produced.

2) CFL (Compact Florescent Lamps  These types of lamps also require a ballast but some of these lamps have a this built into the lamp. CFL bulbs are also known as energy efficient bulbs. CFL's don't give off as much light as HID lamps but due to their energy efficiency and low heat emissions, are highly suited for seedlings, cuttings and early stages of plant growth. They are also available in a variety of colours to simulate different seasons. Typically Blue (6500 Kelvin) and Red (2700 Kelvin).
Kelvin is Colour of light which relates to the temperature of light. The reason for this is simply explained: In the deep of summer months, the sun is very intense and gives off a lot of blue light. During the end of summer, the sun reduces blue light and leaves a lot of red light. Typically we use terminology such as "Cool white" for 6400K & "warm white" for 2700K.

Environment Controlling the Weather

Another advantage we have of growing indoors is further control of the seasons by controlling the environment and ventilation i.e. temperatures, humidity and wind speeds during the day/night. Again this means we can simulate the seasons from anywhere in the world. Giving us the power to grow anything we like (with the exception of anything that grows tall as explained earlier).
We use RVK fans, re-circulating fans and acoustic box fans to control, odours, humidity, temperature and wind speeds. To assist us with these devices we can also use, timers, relays, thermometers, hygrometers, fan speed controllers and even ‘state of the art’ digital fan speed controllers.
Odours produced from plants can be a problem with neighbours living or working nearby an indoor grow room, so we scrub the air that's extracted from these rooms using carbon filters.
In addition to a good ventilation system we can also control the content of the air by supplying our plants with what they need, such as Co2 (carbon dioxide). Intelligent bits of kit are available to evaluate the air in the indoor grow room and control the content of Co2.

Hydroponics Feeding and Watering

We use todays technologies to control the environment of our indoor grow room. We can also apply this to the growing medium and feeding system of our plants. We can choose to grow traditionally using soils which can be made up of a various mixes of minerals, or organic fertilizers of our choice. We can also use hydroponics. Hydroponics is a means of growing plants without the use of soil. This simply consists of nutrient filled water which is made readily available to the roots. There are various methods of rooting to this nutrient filled solution which is explained below:

NFT Nutrient Film Technology. This method consists of the nutrient filled solution passed over a table. The roots simply grow along this nutrient film. The plant usually starts growing in Rockwool cubes and then placed on this table of nutrient film. A spreader mat is also applied over the table to assist the roots and stabilise the plant.

Flood and Drain (Ebb and Flow). The plants are grown in an inert medium such as clay pebbles. This medium is then flooded with nutrient filled solution and then drained, allowing the area around the roots to be exposed by air. The film of water left around the roots after it is drained has a high surface to mass ratio, which means even as the roots absorb oxygen, the high surface area facilitates re-oxygenation which can sustain the roots as long as they remain damp. The high oxygen content also suppresses most harmful pests, thus keeping the root zone disease free.

Drip Irrigation This method of hydroponics consists of inert material such as Clay Pebbles or Coco Coir. The roots are anchored in this medium, which are either in pots or large trays. A drip system is used to pump nutrient filled solution over the top of the growing medium which is made readily available to the roots.

Aeroponics This has got to be the most advanced type of hydroponics growing. It is even used by NASA. Roots are loosely suspended in a chamber. Jets of mist is sprayed around the roots with nutrient filled solution. Because of the great oxygenation of this fine mist of solution, it  allows the plant to have highly oxygenated nutrient readily available. Plants absorb massively more from the air than the oxygen dissolved in water. This leads to explosive growth.

Deep Water Culture (DWC) This is a simple method of hydroponics growing. Roots are directly immersed in the nutrient filled solution. An air pump is used to oxygenate the solution. Once the plant is ready to flower,  the solution level is gradually reduced to allow the roots to be exposed to the air. Plants absorb massively more from the air than the oxygen dissolved in water.

Aquaponics This system is identical to the Ebb and Flow (Flood and Drain) System with the addition of using Live Fish. The by-products produced by fish are filtered out by the plants as vital nutrients, after which the water is cleansed and recycled back to the fish. This is a very natural way of reproducing nature in a perfect Eco Cycle. What better way to grow plants and fish at the same time 100% organic. This system is becoming very popular in the modern home today as we look into eco-friendly and future living.