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Lighting is an important element in any type of marijuana cultivation. The main advantage of growing indoors is that you can recreate the ideal lighting conditions for your cannabis plants and control them as you please. However, when growing outdoors, you depend on your region’s weather conditions. In this post, we'll show you how to choose the lighting system that suits your indoor grow system the most.
Key Considerations:
- Power vs energy expenditure: More power does mean more production, but it also leads to higher electricity bills. The most commonly used lamps are between 400W- 600W, with their corresponding ballasts. LED lights create the same amount of energy at a much lower wattage level, but are often advertised using traditional wattages.
- Temperature vs space: the more watts, the more heat. If your grow tent or room is big, this probably wont be an issue, but if it’s small or you live in a warm area, you may have to invest some money on fans that help you control the temperature.
- Light spectrum vs the time you’re going to spend cultivating: depending on the phase in which a plant is, the light spectrum will be different. During the vegetative stage, marijuana plants need blue light while red light is needed for the flowering. Many growers will change the light bulbs in every stage of their cannabis plants. The blue light during the growth phase will always lead to bigger plants, however, there are other growers who prefer keeping the same lamps during the whole cycle, adjusting only their intensity. While this is possible when you work with sodium lamps, it’s not advisable if you’ve got fluorescent lamps. Most new LED lights will allow you to change between spectrums with a flick of a switch.
Pros and Cons of Each:
SODIUM LAMPS (HPS):
The luminescence of HPS lamps (High Pressure Sodium) is caused by the sodium vapor. There are two types: High-Pressure Sodium lamps, producing a yellow-orangey light, and Low-Pressure Sodium lamps, which provide a rather light-orange light. Both of them are suitable for the flowering phase. There are also mixed HPS bulbs (dual spectrum) that can be used for the growth and the flowering phases.
- Advantages: despite the ever-increasing tendency to opt for LED lights, HPS lamps are still the undisputed queens of the cannabis market. They’re easy to use, they are very potent and guarantee satisfactory yields. And, all that, at a good price. There’re several potencies available ranging from 250 W to 1000 W, the most popular ones being the 400W & 600W bulbs because they offer a good balance between the amount of light they produce and the electricity they consume.
- Disadvantages: HPS lamps present two problems: firstly, they give off a lot of heat and, secondly, their light spectrum is not optimal for your plants’ proper growth. Besides, they wear out over time (they have an average life of a year), so they have to be changed regularly. This kind of bulbs cannot be attached to standard light sockets, so they need a special cover and a ballast, meaning the electricity bill will rise notably.
LED (Lighting Emitting Diode) bulbs are becoming more and more popular among cannabis growers because they offer a marvelous energy-use/heat-production ratio. In the market, there are bulbs ranging from 90 W to 280 W or even more.
- Advantages: Although initially quite a lot of money may have to be invested, the mid-/long-term savings LED bulbs lead to are more than significant. They consume far less energy than HPS lamps and produce less heat as well.
- Disadvantages: LED bulbs are generally more expensive, but as more companies race to the market, the cost of LED lights is decreasing. The significant long-term savings make up for the initial investment, but thehigh price of some high quality LED lamps still restrains many cannabis growers. Their limited heat production can also be a disadvantage for some growers during the coldest months of the year, because they might need to use thermal blankets or radiators to increase the temperature in their growing room.
COMPACT FLUORESCENT LIGHTS (CFL)
Fluorescent tubes or CFL (Compact Fluorescent Light) bulbs are an ideal type of light for the early stages of the plant’s growth, but are becoming much less popular as the price of LED lights begins to drop.
- Advantages: CFL produce the best light spectrum for the growth phase. On top of that, they’re the cheapest because they help reduce your monthly electricity bill. And, last but not least, they’re super-easy to use. Fluorescent tubes are like light bulbs, that is, they come with the typical base. CFL need a ballast, instead, so you’ll have to screw it into the reflector and then, connect it.
- Disadvantages: The low potency of these lamps makes it necessary to install quite a lot of bulbs to properly illuminate your cultivation. Moreover, you may need to set up a system to place them near or far from the cannabis plants, depending on the light intensity you’re looking for. Consequently, the space needed for such type of installation is rather big.