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When you are operating an indoor cannabis grow room, it is important to understand the differences between supplemental lighting and side lighting. Both types of lighting are used to offset certain grow room limitations and increase cannabis plant yields, cannabinoid content, and terpene levels.

So which is better, supplemental lighting or side lighting for indoor cannabis grow?

Our cannabis grow guide on side and supplemental lighting covers the benefits of these lighting techniques and when to use these types of lighting for greater yields with better flavor, aroma, and potency.

Side Lighting vs Supplemental Lighting

In the world of cannabis growing, side lighting is a form of supplemental lighting, but not all supplemental lighting is considered side lighting.

What is side lighting? Well, this is used when you want to target the sides and lower branches of your marijuana plant with enough light to increase the sizes of the marijuana buds on each side.

Since cannabis plants grow denser and larger buds on top, adding lighting on the sides can increase yield on lower branches.

Supplemental lighting, on the other hand, is when the levels of lighting have to be increased for better results or the light spectrum needs to be changed depending on the stage of growth.

Generally, supplemental light is not given to the marijuana plant from the sides, but from above the plant to get larger yields from the top, where cannabis plants focus on their flower bud growth.

Is Side Lighting Necessary?

In indoor cannabis grow rooms, the lighting hangs from above, far enough to avoid burning the plants, but close enough to provide enough light to stimulate photosynthesis.

In outdoor grow spaces, the sun’s rise and fall provide cannabis plants with natural light from above (especially during its peak at noon) and from the sides during its rise at dawn and drop-off at dusk.

Because of the sun's natural progression, cannabis plants tend to grow in a Christmas tree shape. Its triangle shape allows the plants to receive the most amount of light from the sun possible throughout the entire daylight hours.

In addition, the plant’s sloped shape has another major benefit when growing outdoors. Its Christmas tree shape increases the chance that its buds become pollinated. Its lower branch buds extend out becoming more exposed to the wind and, hopefully, pollen from male cannabis plants.

For this reason, some indoor cannabis growers choose to add supplemental lighting on the sides to mimic the plant’s natural growth pattern.

The Light Supplement                                                                                     

It is usually in greenhouses that you would use supplemental lighting. If there is a specific spot that gets direct light in your yard for a few hours each day, you would need supplemental lighting for the hours that direct light is not available in the same spot.

If you live in unreliable weather and you have many cloudy days, then you would possibly have to supplement for extra lighting. You would use a grow light while still benefiting from the natural sunlight.

Importance and Reason for Lighting

Another reason that cannabis growers need to supplement the light in the indoor cannabis grow room is to change or increase the color or spectrum of the light. The light spectrum is instrumental in affecting the way that the plant grows.

LED grow lights are also an option used in many cannabis grow rooms. When you use LED grow lights, you get to select the precise spectrum that you need to supplement outdoor lighting or other lighting such as HPS.

HPS and LED Grow Lights

Today, it is usually very common for cannabis growers to utilize light-emitting diode (LED) grow lights and also common to combine high-pressure sodium (HPS) grow lights with LED panels.

This is for the specific reason of yielding better returns and increasing marijuana flower production. Some cannabis growers use both HPS grow lights and LED grow lights to receive more benefits that good lighting provides.

The Side Lighting

In so many situations, supplemental lighting is an excellent choice. However, it is sure not similar to side lighting, which is not as useful to a cannabis grow room much of the time.

When do you use side lighting?

It is generally used with fluorescent grow lights, an example being T5 grow lights and compact fluorescent lights (CFL). These are used on younger marijuana plants that are not yet trained. Why use these lights in conjunction with the side lighting?

It is because they aren’t powerful enough to get far down into the marijuana plant, which is not ideal, if you want the best bud growth.

Fluorescent lighting is weak enough to only cover a few inches of the plant’s canopy. So, by the time that the marijuana plant is about one foot from this lighting, it is not as useful, but with side lighting, it increases the potential to reach the marijuana buds within a few inches.

Side lighting may also be used by cannabis growers that grow plants in very cramped growing spaces. In these small spaces, the light from above isn't able to effectively bounce from reflective walls to reach the lower branches of the canopy.

In this case, side lighting may be beneficial to stimulate photosynthesis in the lower part of the plants.

On the flip side, very large grow rooms can have certain areas that don't receive the right amount of lighting. In these large-scale facilities, plants that don’t receive enough light aren’t able to metabolize the correct amount of nutrients from its heavy feeding schedule.

Side lighting can help plants stimulate growth, absorb nutrients, and prevent nutrient disorders.

If the cannabis plants are trained to grow shorter and flatter, you will be able to increase the yields using the same amount of lighting since all the main marijuana buds can be shifted to the top while receiving full levels of light.

In other words, although, you may have a weak grow light using fluorescent lighting, you will be able to get more yields by growing the marijuana plants that are flatter and wider in comparison to using side lighting.

When the marijuana buds are close to the top, even a T5 grow light can result in better yields since each bud at the top is closer to the light and because the plant has been trained to lay flat along with the screen.

Are There Better Yield-Boosting Techniques?

Side lighting your cannabis plants can certainly improve your crops yields, but is it the best way to get the highest amount of cannabis buds? Ultimately, it depends on your budget, garden set-up, and growing experience.

Investing in high-quality side lighting can add an additional cost to your existing indoor grow room operation. Adding side lighting may only increase the size of your lower branch popcorn buds by about one-fifth. Consider if this return-on-investment is worth it to you.

If you have the budget and have used all other yield-boosting grow techniques, then side lighting can be an additional and efficient way to improve your crop’s yield. It may not be the most important aspect of your plant’s growth, but it can make a difference.

If you're on a tight budget, there are many additional growing techniques that require no extra costs or very minimal costs to get higher yields. Growing techniques range from low-stress training to Screen of Green to topping and many more!

In short, side lighting can be an exceptional way to optimize your indoor garden when you've done everything else to get higher cannabis yields.

Maximizing Cannabis Yields

Before you run out and invest in grow lights for your side lighting, it is important to start by doing a complete audit of your grow room environment. Often, addressing other grow room limits can provide much more benefits than setting up supplemental side lighting.

Consider the following aspects of your grow room  to maximize your yields:

  • Humidity
  • Temperature
  • Carbon dioxide levels
  • Watering practices
  • Nutrient uptake

One of the best ways to improve your yield is to employ a variety of cannabis plant training techniques. Techniques vary in sophistication, but they all work on the same concept of increasing horizontal growth and splitting the plant’s apical dominance growth.

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Common plant training techniques include:

  • Low-stress training (LST)
  • Sea of green (SOG)
  • Screen of green (SCROG)
  • Lollipopping
  • Topping
  • Fimming
  • Mainlining
  • Supercropping
  • Defoliation

Supplemental Lighting or Side Lighting for Indoor Cannabis Grow Recap

Side lighting is a kind of supplemental lighting but supplemental lighting is not a kind of side lighting. Depending on which lighting you chose for your grow room depends on your specific needs and room set up.

Use side lighting if you want to target the sides and lower parts of the plant. Think of supplemental lighting as needing to supplement your exsiting lighting with extra lighting. It may not always be needed but is there when/if you need it.

Become a Cannabis Growing Expert 

If you want to know more about the use of supplemental lighting and side lighting in your indoor cannabis grow, visit the Cannabis Training University today.

Cannabis Training University is the world's most renowned and affordable online industry training programs for students of all skill levels.

Whether it's your first time growing a plant or you're a seasoned grower looking for new techniques to take your garden to the next level, CTU provides you with the most up-to-date information at an affordable cost.

Become a marijuana growing expert by enrolling in CTU's marijuana courses online today!

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