The main reason for me to start writing an Internet 'course' was the fact I
wasn't satisfied with the information on growing weed that was available at the time.
Also in talking to people I found out that a lot of them don't have a clue about
the main issues in growing plants and focus on the wrong things.
I learned the 'art of growing' by one of the best 'teachers' and always remember one thing he told me:
"Bonk, in fact it's a very simple thing to do. You take care of the plant and the plant takes care of you".
Well maybe this simplicity falls in the same category as riding a bicycle, here in Holland any kid knows how to do it, so we don't understand if someone's not able to stay on one of them things. (On the other hand I don't know how to ride a horse since I can't find any brakes on them.)
Let me start with some of the basic facts on growing plants.
Like any other living thing on our planet, a plant needs water, air, light, food, and warmth. Take one of those things away and your plants won't grow. These are the main factors in growing anything at all. You could have a perfectly built greenhouse but if your plants don't get any water they die.
More than 75% of a plant's weight is water.
Besides being used as transportation-medium, about 99% of the water absorbed by the roots will be used to keep a plant cool.
This works the same as with us human beings: by evaporating water, heat is absorbed which results in a cooler body.
The remaining 1% will be used in the plant's photosynthesis process. Photosynthesis is a complicated process where the plant builds carbohydrates from water, CO2, and light-energy. These carbohydrates are later combined with other chemical compounds absorbed from air and soil and transformed into new plant substance.
Also, 'additionally' Oxygen is formed as a waste product.
This process is the start of the food- and air-chain; plants play a very important role in life as we know it.
It seems that everybody understands the importance of light and water in the process of Photosynthesis.
But the third factor, being CO2, is always underestimated.
I won't go into much detail here because you don't have to know what makes an engine work to drive a car, but have a short look at CO2.
This formula tells us Carbon Dioxide is a molecule made of one Carbon and two Oxygen atoms. The Carbon atom is of importance here (Oxygen was just waste, remember? If life would be that simple ;-):
the problem is that there is only one Carbon-atom in each molecule. Also you have to keep in mind that there is only about 0.3% CO2 in normal air. So maybe now you understand why air is of such importance.
Let's make a quick jump to light.
As I already told you the energy of light is used to form carbohydrates like sugar, starch and cellulose.
Of course this can only take place if there is a source of light available. The light we see from the sun is a mix of all colors. Plants use mainly blue and red light, depending on the growth stage.
So here we get another problem, since we are growing indoors where the sun refuses to shine we have to use another light source.
One problem is that normal bulbs don't give enough light for a plant, but the main problem is they have the wrong color. At this moment the only lamps giving enough light in more or less the right color are Metal-Halide bulbs.
For the vegetative (= growing) stage of a plant's lifecycle you need more of the blue light. You could use high-pressure mercury lamps but since growing doesn't take that much light and you are probably only growing your own seedlings or clones you could just as well use fluorescent tube lights (color cool white).
Flowering marihuana asks more red light which seems to be more of a problem.
At this moment, and as far as I know, the best results come from high-pressure sodium lights.
The best you can get are Philips® Sun-T plus bulbs, and I don't say that because I'm from Holland (they are made in Belgium anyway).
Another thing that has to do with light is Photoperiod,
the relation between the length of day and night in a twenty-four hour period.
Marihuana is a short-day plant, which means it will start flowering at twelve hours light and twelve hours of darkness.
Long-day plants will do their thing after they have reached a certain age, but let's stick to short-day plants.
Although marihuana is a one-year plant you can force it in a certain growth stage by 'fooling' it with the length of light. Change the period to 12/12 and it will flower, keep it at 18/6 hours light/dark period and it will grow 4ever.
Okay, we have had light, water and air. Let's go eat.
After eating, our meal is digested in our stomach. Another weird chemical process involving things you may not want to know about. Because our cells can't do anything with let's say a piece of banana, it's ripped apart in molecules and elements which our body cells know how to handle. Among other things acid is being used to split complex molecules into easier to handle smaller molecules and elements.
The same goes for plants, they can't nourish on the complex molecules you'll find in the medium at which they root, be it soil or rockwool. Because they are not equipped with a stomach they're in a bit of a disadvantage, their food has to be pre-digested so to speak. And although a plant is not as helpless as you might think, it helps to keep the growing-medium a bit on the acidic side of the famous pH scale so your baby's roots won't have such a hard time picking up nutrients.
And finally; since eating and growing means work and all work costs energy this is where warmth gets in. If a certain temperature is not reached, there will not be enough energy for the process to start up, or things will happen at a lower rate. This is especially true for roots; the temperature at the roots should be at a minimum of 20 degrees Centigrade to a maximum of about 28 degrees. Air temperature is mostly not a problem, keeping your feet warm is of more importance.
Now all of the above; water, air, light, food, and warmth are essential growing-factors. They all have to be in order or you will find that things won't go as planned. Building a good environment is our first goal; I'll cover that on the next pages.
Simple isn't it?
Like I said, just like riding a bike.
To convert Centigrade to Fahrenheit: C x 1.8 + 32 = F
Learn more about photosynthesis at the Arizona State University.