How to choose the best lighting system for your indoor cannabis cultivation

There are many types of indoor lighting systems. Whilst it's true that some are more popular than others, the adequacy depends on the circumstances and on the grower's needs. The space available, the outside temperature, the financial resources or the grower's experience are factors that need to be taken into account before choosing one system or another.

What should you bear in mind for choosing a lighting system for your cannabis cultivation?

• Power vs energy expenditure: this point is indeed very important. More power does mean more production, but it also leads to higher electricity bills. The most commonly used lamps are 400 W and 600 W lamps, with their corresponding ballasts.
• Temperature vs space: the more watts, the more heat. If your grow tent or room is big, this won't probably entail any disadvantage 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, however expensive this could end up being, of course. We've also got the opposite case: should we buy a low-calorific lighting system, you are likely to need thermal blankets or radiators to keep the temperature steady all the time.
• 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 the red light is needed for the flowering. That's because red tones better mimic the type of sunlight that there is during summer and autumn. The blue light is more similar to the gentle light typical of the preceding months. Many growers have the time and the will to change the light bulbs in every stage of their cannabis plants. And all that effort is not in vain. The blue light during the growth phase will always lead to bigger plants and more numerous branches. However, there are other growers who lack the time and the will and 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.

Lighting systems for your indoor cannabis cultivation

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 400 W and 600 W 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.

Fluorescent tubes or CFL low-consumption bulbs

Fluorescent tubes or CFL (Compact Fluorescent Light) bulbs are an ideal type of light for the early stages of the plant's growth. There are also warm CFL that produce a red light which is perfect for the flowering phase. Normally, fluorescent lamps range from 18 W to 55 W, while CFL bulbs are usually 100, 125, 200 and 250 W.

• Advantages: Fluorescent tubes and 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.

LED bulbs

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 expensive. Very expensive. As previously stated, the significant long-term savings make up for the initial investment, but the high price of these 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.