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Spectrum: Which is Right for Cannabis?

Growing any type of plant can be difficult. Cannabis, in particular, is extra complicated, as it relies on strict light/dark cycles to grow in precise ways. Along with these cycles, the cannabis plant thrives on varying light spectrum stages depending on the plant’s phase. While some growers may try to convince you that one stage of the light spectrum is better than the others, we’d have to disagree.

Here, we’re talking about the right light spectrums for the cannabis plant and how beneficial it can be when you take the time to utilize these in your cultivation. From UV rays to green lights to bright red ones, let’s discuss the ideal spectrums for your home-grown cannabis.

Different Lights for Different Phases

As we mentioned above, there isn’t one specific type of light ideal for the cannabis plant year-round. The natural light spectrum changes and adjusts based on environmental factors and time of day, exposing plants grown outdoors to these consistent shifts. Many growers realize that replicating these light changes using different light spectrums creates the best results at the end of their harvest.

By mimicking the sun’s actions and light waves, cannabis plants grow strong and healthy all on their own. Unfortunately, this creates a lot of extra work for the grower, as you will need to invest in various types of lights that can be switched when needed. However, this added care results will be more than worth it at the end of your cultivation season.

Now, let’s talk about the different light spectrums and which cannabis plant phases they are ideal for.

UV Rays

UV rays technically fall under the non-visible light spectrum, meaning we don’t pick up on these wavelengths just with the naked eye. However, we know they’re there, as these are the same intense rays that can cause us sunburns. While they may be a bit painful and sometimes dangerous for our skin, plants like cannabis sure seem to love UV rays.

While this hasn’t been proven, it appears as though UV rays are excellent for helping boost THC production in growing cannabis plants. Specifically, farmers see the best results when used during the flowering stage of the cannabis plant. During this stage, the plant is producing the resinous buds that give value to the plants. The higher the THC contents in these buds, usually, the better the cannabis you’ve grown. High levels of THC are always sought after with cannabis plants, and finding ways to enhance these levels is a game-changer for cultivators.

If you do attempt to boost THC production through UV rays, make sure to do so delicately. As we mentioned, this should be done during the flowering phase when the plants are producing their buds. Ensure that these lights are not placed too close to your plants, as these UV rays can burn your plants’ leaves, effectively impacting color, potency, and taste. With the UV light spectrum, you have to create a delicate balance to enhance that psychoactivity.

Blue Light Spectrum

Next comes the blue light spectrum. Generally, most farmers choose to use their blue lights during the vegetative state of their cannabis plants. During vegetation, your cannabis plants will be doing most of their growing, sprouting their leaves, and finally gaining some height. If you were growing your plant naturally outdoors, the sun would likely start to emit blue light during the spring and summertime, letting your plants know that it is time to vegetate. Thus, farmers replicate this natural phase by shining blue lights on their plants as they grow.

This kind of light use has shown profound benefits in terms of growth. Doing this helps your cannabis grow bigger, stockier leaves that are much better for cultivation than thinner, more brittle ones. Along with this, research has found that blue light exposure is healthy for your plant’s pores, promoting natural regulation to soak up the carbon dioxide.

In general, you should always make sure your plants are getting some kind of blue light during their life cycle. During the vegetative state, though, it is easily the most effective choice.

Green Light Spectrum

Green light is one of the most critical colors on the light spectrum for your cannabis plants. This color has been found to promote overall plant growth, and it is beneficial to use it throughout various stages of the plant’s life. Thankfully, plants can pick up hints of green in other light spectrums like red and blue, helping them get the full range of spectrums that they require.

Some farmers choose to use green lights right at the seedling phase when their seeds are just beginning to sprout; others prefer right at the end of vegetation. Others, still, boast about the benefit of green lights during flowering! The green light spectrum is a versatile one that can—and should—be used throughout cultivation.

Cultivators love green lighting because it’s one of the only stages on the light spectrum used in the dark. When shone on plants, green lighting doesn’t disturb a plant’s light/dark cycle, keeping them resting as they should. This is great when you need to analyze your plants up close, but you don’t want to mess up the light/dark cycle you have established.

Red & Far-Red Light Spectrum

Finally, red and far-red lights are typically utilized during the flowering stage of your cannabis plant. In nature, the sun will produce more red light during the end of summer and early fall, letting plants know that winter is quickly approaching. This signals kind of the last growth effort, helping your cannabis begin to bud. You might even notice your plants’ stems elongating and making room for more flowers after exposure to red lights in the flowering stage.

Make sure to be balanced with your exposure to red lights, though. Too much red light can cause your plants to grow too much, becoming more elongated and sporadic than they should be. This sort of growth can ruin your plant’s composition and potentially even that plant as a whole. Instead, give your plant proper doses of red light similar to how they would be exposed during the summertime. Then, as temperatures would cool naturally, do the same with your lights. This helps to ensure not only healthy growth but more significant, more potent results, too.

The Right Lights for Cannabis Plants

It might take a little bit of time to perfect, but understanding the right color spectrums for the proper phases of your cannabis plants can take your harvests to a whole new level. The most important thing to remember is that, out in nature, cannabis wouldn’t be subjected to just one lightwave, so why do that when growing your plants indoors? Variation is key.

Here at Luna Cultivation, we understand how tricky these spectrums can be. But, as experts in the cannabis lighting industry, we’re always here to help. Check out our other blogs on cannabis lighting and, soon, this will all become second-nature.

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