For a start, we need to ensure that the space is made completely light-proof. In order to bloom to its peak the cannabis plant needs 12 hours of undisturbed night and 12 hours light. Disrupting the 12-hour night period leads to lower yields or even completely failed harvests. That’s why you should go stand in your space if this is possible and take a look to make sure that no light is creeping in. If there is, then you can get a special light-proof tape that will blot out the holes and cracks. A grow space that is not lightproof can easily mess up your harvest because the plants will become confused. One of the most easily preventable things that can happen is the creation of male flowers on the female plants thanks to the stress they have been exposed to. In no time at all just a few male flowers can fertilize the whole female planting, with the result that you end up with buds full of seeds.
*watch out for male flowers and light leaks!
A good grower always checks his plants so that he can remove any male flowers in good time. It takes a few weeks before a male flower can disperse active pollen. It also happens frequently that the plants find it difficult to come into bloom when beams of light are allowed to get in and they will as a result in a lower yield. Above all watch out that any electrical appliances left in the grow space or destined to be left in there, because these usually have tiny lamps that give off a lot of light that can disturb the night’s sleep of your plants. Stick a piece of light-proof tape over any lamps and lights.
Once cannabis plants are well and truly in bloom and are producing gorgeous resin covered buds, the development of their aroma will also begin to Increase. Cannabis plants will begin to spread a fragrant and somewhat powerful aroma, which makes it vitally important that our grow space is also made fully airtight. The grow space must have a minimum of cracks or holes in it from which the aroma can escape, and preferably absolutely none. Once your plants begin to smell then you will probably be visiting your crop so regularly you will get quite used to it (nose blind). In this way you can become convinced that your plants are making little to no smell, when in fact neighbors or fellow inhabitants are potentially noticing the stench. One other important factor in addition to the safety aspects of having an airtight space is the control of the climate. Creating a good climate is enormously important if you want to get the very best from your plants. Make sure when you are setting up your space that unwanted smells can neither get out nor drafts find their way in. A third important point is that any undesirable creatures and vermin cannot find their way in to your space. A good grow space is in effect a kind of quarantine cell in which nothing gets in or out without your say so.
Once we have the previously described points firmly sorted out then we have arrived at our eventual goal of setting up the grow space, creating an ideal climate in which our plants can develop into real giants, growing and blooming at unheard of speeds. Because the climate has to be constant and even throughout your grow space we need a ventilator (or more than one) to make sure there is a good air movement. The plants will also grow thicker and stronger and will at the end yield more than plants raised without ventilation. If you have a good budget at your disposal then you might want to invest in a thermostat, hydrometer or a thermo-hydrometer. You can connect up the thermostat to the exhaust ventilator, which will allow you to set your desired maximum temperature – say, 75 degrees F – for your space. If the temperature rises above that, then exhaust ventilator kicks in to bring it back to 28 degrees. The hydrometer can also be coupled to the exhaust ventilator to make sure that the required air moisture content is maintained. If your space becomes too humid then air is sucked out until the right level is reached. With a dimmer switch you can regulate the speed at which the ventilator operates, so you can run it continuously at a slow speed to keep fresh air pumping into your space.
In order to regulate the air moisture content we will need an air humidifier. They are not too expensive and well worth the investment. The nice thing about them is that they usually come with a built-in hydrometer so that you only have to punch in the required air moisture and the humidifier takes care of keeping it there. Especially during the growth period this works wonders. A plant can double its rate of growth in humid air, and this will help reduce the time spent in the growing phase. Warming a large room or a small growing space will make a world of difference. Letting the air moisture rise during the first weeks is easy in a small space, but try it some time in a whole room. It’s just as easy in a large space but then you will need a whole load of expensive equipment and as a beginner you ‘re better off trying to keep your set up low budget. Now you can just as well throw some decent money at getting your space well insulated; each to his own. We also need to make sure that on one side of the space, down at the bottom, there are holes for air to enter. These holes are to let new CO2-rich air get in. On the other side of the space, right at the top, is where we place a suction pump. This will suck up and remove the warm air. Warm air rises, which is why we place the pump at the uppermost point of the space, or at least the highest possible place. By fitting a carbon filter to the suction pump we can remove at the same time any strong aromas. A carbon filter and vacuum pump go together hand in hand and are absolutely essential in a garden set up such as we are building. A filter will suffice for around five harvests, or about a year. The pump must be of appropriate capacity for the size of the grow space, so first you have to calculate the volume of that space. Casting your minds back to school, we know that multiplying length x width x height will give you the volume of your space. Always take a pump with a slightly larger capacity than the actual volume of your space. During the hot summer months this can make a big difference in keeping your growing space at a reasonable temperature.
The great advantage of this is that during the cooler winter months we can let it run gently and using little energy, the during the hot summer months we can let the throttle out and comfortably keep the temperature below 30 degrees. A large ventilator running at half speed makes a lot less noise than a smaller ventilator running flat out. Also, should you wish to increase the size of your grow space in the future then there is no need to buy a new ventilator. You can never buy a ventilator that’s too large, only one that is too small. It makes little sense to keep a ventilator running flat out if it can keep the space replenished with new air at half speed just as well. By placing the air intake holes at the bottom of the space and the exhaust at the top you create an air stream that will carry the new, enriched air from below, right up to the top on the other side of the space, flowing over the plants as it goes. This is great for the plants, which can enjoy the fresh air to the max before it is depleted of CO2, sucked away and removed from the space. In order to keep pests outside we can use a Nylon stocking or special socks placed over the air input holes so nothing can fly or creep in, which will help you avoid an infestation later. Certainly do not forget either that no light must be allowed to get in through these holes to reach the space. PVC tubes with a bend in them work well to let air in but keep light out. There are thousands of ways of making sure there is a good air supply to your space; they’re all great, but there are two main rules to bear in mind: by preference, air in at the bottom, and keep it light-proof. In a situation where you simply cannot make a hole for the fan anywhere then the best solution is to buy a cheap door and make a hole in that for air extraction. This is a frequently used method by professional growers.