The Grow Room
You can look for a suitable grow room or build one yourself. It is necessary for your growroom to be lightproof; cannabis plants can’t flower without 12 hours of uninterrupted darkness. You also need good airflow in your room. The plants evaporate a lot of water during the flowering period and to prevent the forming of bud rot you need to exhaust the wet air. During the light cycle your growing light will be producing a lot of heat, which means that you need fans to keep the temperature down.
Keep in mind that you choose a place that stays a bit cool during the summer. The best place for growing marijuana indoors is a place has few problems with heat waves during the summer. The attic seems to be the ideal place for a lot of people for growing marijuana indoors, but most of them become very hot during the summer months, which means that it gets difficult to achieve optimal results. The quality of indoor weed is often lower after the summer, because growers aren’t capable of keeping the temperatures in a respectable range.
The size of the grow room is dependent on your demands and limitations. Do you want to grow just enough for you and your friends or do you want to make a living out of it? Perhaps you just have a small room in which you only have space underneath your desk to place a small box with just one plant that stays very short (probably a lowrider). Whatever the size of your growroom is going to be; make sure that there is proper airflow and that it’s lightproof.
While there are optimum conditions to aim for in your grow room, it should be noted that it is more important that your ranges aren’t too extreme. Often too hot while the lights are on and then too cold when the lights are off; these types of dramatic differences will negatively affect your grow.
The Growing lights
The types of lights you’re using have the most impact on the final yield of your plants, HPS, LED and Fluorescent are popular choices. Of course the number of lamps and the wattage of the light will determine your final output. One grow will take around 10 weeks. A short period of pre-grow in which you cultivate the plants to a certain height and afterwards the flowering period that will take around 8 weeks for most strains. You have to ask yourself: how much marijuana do I need during this period?
Most growers use HPS and MH (High Pressure Sodium and Metal Halide)-lights because they are for the time being still the standard. The spectrum of hps is especially suitable for flowering (red-orange light) while MH (cool white / blue light) is used during the vegetative period (although both can be used in combination during any stage). The light-effectiveness is very good with an amount of 150 lumen per watt for a hps 600W. They come in different wattages and the most used examples are 250W, 400W, 600W and 1000W. As a starting grower, you have to count on half a gram per watt if everything goes fairly OK. So with a 250W hps you probably should get around 125 grams. Hps lights require a very powerful ignition current which means that you can’t just plug your light into a simple five dollar timer because they can only handle a maximum of around 10 amps, so make sure you use a switch box for that. In theory, a hps light that burns 12 hours a day will lose 20% of its efficiency in a year, this means 20% less yield. The lifespan is around 24.000 hours and most of it’s decline is due to the switching on. It’s more profitable to replace the light when it has lost 20% of it’s original light-power, than to save costs on the purchase of it.
Minimal distance between light and plant:
- 250Watt: 25cm/9,8”
- 400 Watt: 45 cm/17,7”
- 600 Watt: 55 cm/21,6”
- 1000 Watt: 90 cm/35,4”
A LED growing light exists out of a group of LEDs (LED = Light Emitting Diode). LEDs are very sustainable and have a lifespan of more than 50.000 hours. The growing light is built up around different color LEDs to provide the right spectrum for growing and flowering. Growing requires more blue light, which means lots of blue LEDs. Flowering depends primarily on red LEDs, but to achieve good results there are more types of LEDs needed during flowering.
LED growing lights are on the rise, but they are still very expensive and don’t always deliver great results. Though there are some very good options available that deliver great results and are worth the extra costs on the long-term due to the lower energy bills. Another benefit of using LEDs is that they have nearly no heat-development which means lower temperatures and fewer humidity troubles – and of course less risk of fire. LED lights can be turned on and off with a simple cheap timer.
Distance between light and plant:
- Somewhere between 5-10cm /2-4” dependent on the amount of heat that they produce.
Fluorescent lights are very efficient but have a low lumen output, which means they don’t need much current but they also won’t deliver you massive buds. They are great to use during the growing period but during flowering they are far too weak to deliver a good yield. They need to be placed close to the buds to be in any way effective. It’s a good option for a beginner grower that doesn’t want to invest too much time and money. You can find them in every DIY shop or regular lamp store.
Distance between light and plant:
Cool white light means healthy growth, yellow light is important during the flowering period. Fluorescent lights are capable of delivering good white light, but to use them during the flowering period is not recommended, although the small amount of energy fluorescent lights consume can be an advantage. The same applies in a minor degree to LED lights; there are types available that deliver good flowering results, but a lot of them come short of expectations during flowering while growing went great. HPS lights are the best for flowering due to the large amount of red-orange light, but they will also do great during the growth.
One factor that is underestimated often is the way the light beam reaches its target. In an ideal situation all the plants are growing uniformly, so they need to get the same amount of light. To achieve this you can use a reflector above your growing light to spread the light beam.
A very important element of growing marijuana indoors is controlling the climate in which your plants will grow and flower.What you will need is an exhaust-fan, placed at the top, that will blow the air outside and makes sure that fresh Co2 rich air will enter your growing space through air hole placed at the bottom. You can also add an extra fan for the intake of fresh air but this isn’t necessary (you can easily add one when you temperatures require it). You can go for a powerful tube exhaust fan that you can find in every DIY shop, or when you want to keep things very quiet, a low noise computer fan will do the trick.
You can use a carbon filter to make sure that the smell of your plants isn’t coming out of your growing space when growing marijuana indoors. Such a filter can be used for about one year. It’s best to buy this filter together with your exhaust-fan because it has to fit perfectly and with a certain exhaust capacity belongs a certain capacity carbon filter. Make sure the filter is placed before the exhaust fan instead of behind, or else the air will go across the filter too quickly and smell will come through. Make sure you always use a carbon filter and refresh it every year. Maybe you won’t smell your plants because you’re used to it, but maybe others such as your neighbours will think differently about that.