Plants & Carbon Dioxide
Everyone is aware of the important role plants and algae play in our ecosystem. Plants make it possible for life to exist on earth. Plants are in fact the givers of life. All life on earth depends on plants and algae, not only for food and shelter, but most importantly for oxygen. Whether life on earth may have adapted and evolved in a completely different direction without plants is unknown, and will probably never be known unless the day comes when plant life can no longer be supported on earth. In that case it is more than likely there will no longer be human life available to study and document any further development. It is an important fact, you and all life on earth only exist because plants and algae exist.
Put simply, plants “breathe” CO2 and produce oxygen in the process of photosynthesis. All plants require CO2, some plants, one popular ancient plant, a plant that is now unreasonably illegal is a CO2 consuming machine. If this plant were put back into agricultural use it could possibly counter all man made CO2 and end all forest destruction. This plant is so efficient, a few acres of it can replace an entire forest of trees, but we've chosen synthetic over natural and forest products over the possible alternative of using this “vile weed”.
In most gardens a CO2 level of 1000-1600 PPM is ideal. This can increase growth production up to 40% if done properly. Things get a little more complicated in enclosed systems. In nature everything is pretty well balanced, but in an enclosed system you are left to control and monitor everything. In small enclosed spaces things happen quickly. This is especially true when living matter, such as plants, are incorporated. You would not be comfortable in an enclosed space without a supply of fresh air, your plants should be considered the same. Without a fresh supply of air they will quickly use up all available CO2 and become stressed. Your greenhouse or indoor garden should be completely replenished with fresh air every hour. This can easily be accomplished with a fan timed to switch on every hour for as long as it would take to exchange all of the air. To determine what size fan is needed to accomplish this in a reasonable amount of time, you must calculate the cubic area of your garden by measuring the area and multiplying the length, width and height in feet. If your growing area is 10'x10'x10' you would have 1,000 cubic feet. In order to completely cycle the air in a small amount of time you would need a fan capable of moving 100 CFM (Cubic Feet per Minute) set to power on for 10 minutes every hour. Keep in mind that in order for fresh air to come in old air must be released through an exhaust port on the opposite side of your garden. If your garden is in a small area such as a closet or grow box nothing larger than a small computer fan is needed, provided it is capable of moving the proper cubic feet of air per minute.
While simply having an exhaust system built into your garden will provide enough CO2 for plants to survive, introducing CO2 through other methods can almost double plant production. Introducing CO2 to your indoor garden or greenhouse is pretty simple and well worth the effort, and there are several ways to do it. One popular method is purchasing compressed CO2 in a tank, although purchasing large amounts can draw unwanted attention. Most shops have an exchange system where you borrow the expensive tank full of gas, leaving a deposit for the tank and paying a surcharge for the CO2 gas. When the tank is empty you simply exchange it for a full tank once again paying for only the gas. The reason some shops do this is to be able to offer CO2 without the heavy cost of having a distributing system and the inherent danger that comes with the distribution of compressed gas.
If you choose to use a compressed CO2 system to supply CO2 to your garden, you will also need a way of distributing the CO2 throughout your garden. This will consist of a CO2 tank and a regulator. The least expensive regulator simply releases a small flow of gas constantly. More expensive systems incorporate a solenoid that automatically opens and closes the gas supply. This can be accomplished with the use of an electric timer. More advanced systems use a device that monitors CO2 levels and adjusts them by either opening or closing the flow of gas, similar to a thermostat that monitors and adjusts the temperature in your home. A small electric fan can be used to evenly distribute CO2 throughout your enclosed garden.
Another way of introducing CO2 to your garden is the use of a homemade yeast CO2 generator. A lot of people are now using alcohol fermentation to their advantage. Alcohol fermentation is pretty complex, but all you need to know is that as yeast consume sugars, CO2 and alcohol are among the many waste products produced. Although on a large scale this method would be way to expensive, it's use in a small enclosed area like a closet or grow box should not be overlooked. Building a yeast CO2 generator is pretty easy, and a good method is to simply mix half a gallon of warm water with a packet of bread yeast and a pound of sugar in a one gallon milk jug. Drill a hole in the lid and connect a length of aquarium tubing that can be placed behind a fan that will distribute the CO2 throughout your garden. This will generate CO2 for about a week. The yeast can actually be reused a few times. Just pour out the liquid leaving behind the yeast cake on the bottom, and mix in more sugar and warm water. Fermentation does produce allot of foam that can easily travel through the tubing, and if you are worried about this an overflow reservoir can easily be added.
An often overlooked source of CO2 is humans. although not very efficient, you produce CO2 every time you breath. Have you heard the old wife's' tale that talking to your plants is beneficial? It's true! Every time you speak you release CO2. So, if you haven't considered putting your CO2 eco-waste to good use, then perhaps you might. Although we can't live in our greenhouse or garden, just by working or sitting for an hour or so will introduce a lot of valuable CO2.
