You are currently viewing The LED learning curve for cannabis growers: Four things you need to know

The LED learning curve for cannabis growers: Four things you need to know

Indoor cultivation of cannabis has been around for decades, and it’s mostly been grown the same way –using the same type of lighting. But technology has changed and many cannabis growers are learning that LED grow lights have many benefits.

It might seem intimidating for cannabis growers to change everything they know about grow lighting and embrace new technology, but the future of indoor cultivation of cannabis is rapidly growing and the industry is changing.

Using high-pressure sodium bulbs (HPS) to grow cannabis indoors is outdated, costly and –it’s on its way out. Cannabis growers who embrace LED grow lights will see many benefits.

So, what’s the LED learning curve for cannabis growers? What do growers need to know about making the switch? Here are four things to consider.

Energy savings

One of the first things cannabis growers will notice when switching from HPS bulbs to LED grow lights is a dramatic energy savings. That’s because LED lights use far less energy than HPS lights. But that’s not the only reason for the savings. HPS bulbs burn hot, meaning growers have to compensate for that heat in an indoor environment by adding ventilation systems and HVAC systems – which are not cheap to run.

Generally speaking, LED lights cost about 50% less to run than the equivalent HPS lamps.

LED grow lights offer other environmental benefits as well, and growers that use them typically do not need to use as many pesticides or chemicals on plants because LEDs allows growth to take place in a highly controlled environment.

Also, LED grow lights don’t contain mercury, a toxic substance. They also have a longer life than HPS lamps, meaning less waste in the landfill (HPS bulbs require frequent changing).

Control – and tuning

Indoor cannabis growers know the industry is changing. Gone are the days when you could place all your plants on a flat surface and take up a ton of space. Cannabis is slowly turning into a commodity crop now, with many states legalizing it, meaning craft growers need to think more like large-scale crop growers. And one way that this is happening is by growing UP not OUT. Racking systems are a way to put more plants in a smaller space than just spreading them out and the cannabis industry is starting to embrace this vertical farming technique that is already widely in use in other crop-growing operations. But to do this, cannabis growers need LED grow lights. Why? Not only do HPS grow lights burn hot and don’t distribute light in the same way, their form factor doesn’t have a low profile. LED grow lights permit the grower to put them within 6” of the plant depending on the manufacturer’s design and engineering.


Because an LED printed circuit board can be designed or ‘tuned’ for a specific application such as vegging, flowering or both some manufacturers offer cannabis growers more than 1 recipe of spectrums depending on the intent of the cultivator.


cannabis growers
cannabis growers


Vegging and Flowering
Metal Halide
High Pressure Sodium

On the other hand, high pressure sodium and metal halide lamps offer only one spectrum.  As you can see by the graphic, the metal halide spectrum is skewed toward the blue end of the spectrum while the high-pressure sodium is skewed towards the red.  Neither one offers much white light like the sun.

The Photosynthetic Equation

LED grow lights also impact the nutrient needs of the plants grow underneath them. Many cannabis growers first making the switch discover that their plants require more nutrients to grow optimally. Plants grown under LED grow lights tend to mature a faster rate due to the more complete spectrum which means nearly everything else must be adjusted as well including supplemental CO2, water, and air flow. Dialing in the environment takes time but is well worth it for the best yields.

The Key Takeaway for cannabis growers

The cannabis industry is growing and changing at a rapid pace. And cannabis growers who do not embrace technology – like LED grow lights – could get left in the dust by those who do. Ask any business owner who didn’t make the switch when new technology came out – if they are still operating.

LED grow lights are the future and cannabis growers would be wise to make the switch now, to stay ahead of the pack.