Grow Light Spectrum Compared Full-Spectrum vs Broad-Spectrum LEDs

Cannabis Light Cycles

When speaking of either full-spectrum or broad-spectrum LEDs, The Center for Environmental Therapeutics says, “The terms ‘full spectrum’ and ‘broad spectrum’ are not precise technical terms.”

Full and broad spectrum refers to the range of light waves found in LED grow lights. It also relates to full versus broad-spectrum CBD, which comes from cannabis. You’re going to need lighting that’s specific to the plants you want to grow.

Is there a difference between full-spectrum and broad-spectrum grow lights?

Some explanations of full-spectrum light indicate that full-spectrum LED lamps imitate what you get from the sun. This includes both visible and invisible light rays.

The visible light rays present the seven colors of the rainbow that we can see. Invisible ones include ultraviolet (UV) and infrared rays (IR) that we can’t see without special viewing tools.

Concerning full-spectrum lighting, fluorescent lamps may emit more UV rays than LED ones do. However, the Department of Energy does indicate that LED lamps can emit all three types of UV rays, which include UV-A, UV-B, and UV-C. They also may radiate some IR waves.

As far as whether plants require UV rays for growth, that’s a debatable topic. Some sources say “yes” and others say “no.” The team here at Boya would tell you that having some of the natural UV rays like what plants would receive from sunlight couldn’t hurt – at least not in moderation.

As far as monitoring how much UV and IR radiation your cannabis plants experience, that’s up to you. You can control your environment more than you could if growing outdoors when you set up your grow lighting systems right.

For now, we will move on to the full-spectrum and broad-spectrum CBD types, which often make use of full-spectrum LED grow lights.

Before we do that, however, we will briefly mention that some sources describe “broad spectrum” LEDs as lights that don’t have UV rays. Other researchers have defined full spectrum and broad spectrum LED lighting as being synonymous–that both of these terms have the same meaning.

Whatever you choose to believe about LED lighting, you need to have the ideal spectrum for producing cannabis. Otherwise, you won’t be able to grow the yield required for developing either full-spectrum or broad-spectrum CBD extracts for your cannabis products.

About Full-Spectrum and Broad-Spectrum CBD Extracts

Besides lighting, full- versus broad-spectrum also refers to the two different types of CBD you can grow. Both types of CBD can grow using either full-spectrum LED lights or specific colors of the light spectrum, which usually are red and blue.

It may take you some careful strategizing to decide what lights to use and when, but you’ll get the hang of it soon. If you have any questions along the way, please contact one of our Boya team members for assistance. Now, we describe full-spectrum versus broad-spectrum CBD.

What is full-spectrum CBD?

The National Library of Medicine (NLM) explains that full-spectrum CBD uses extracts that contain the following elements: CBD, flavonoids, terpenes, essential oils, and other cannabinoids. The THC concentration usually measures less than .3%.

What is broad-spectrum CBD?

The NLM describes broad-spectrum CBD as having all the components of full-spectrum CBD but is “nearly THC free.” However, the .3% THC or less that shows up in full-spectrum CBD as “nearly THC free” seems like nothing at all. For that reason, sources such as Healthline consider broad-spectrum CBD as a type with “No CBD.”

What about isolate?

We didn’t mention “isolate” yet. It’s a third type of CBD that doesn’t contain any other components of the cannabis plant from which it was derived. On the contrary, both full-spectrum and broad-spectrum CBD extracts may have other parts of cannabis plants in them.

Does it matter what kind of light you use for CBD?

Many factors play into what type of light you would use for CBD. For instance, you may end up growing some Bubba Kush, Northern Lights, Lifter, or another Cannabis strain. Each one of these or other strains you grow will have its unique qualities.

If you’re in doubt about what type of light you should use for your strains, start with a full-spectrum LED. Besides, some full-spectrum lights will also allow for growth light spectrum adjustments. This will benefit you come time to decide the proper ratio of blue to red LED spectrum ratio.

If you’re not using the full spectrum grow lighting, try for a 3:1 or 4:1 red-to-blue ratio. You can always monitor your plants and make adjustments later.

CBD Grow Light Considerations: How to Choose

When you do research on what CBD lights to install, you may end up reading some biased reviews. They may provide you with some useful information, however. For instance, we just found some grow light marketers making these suggestions for grow light considerations.

1. Measure the size of your growing area.

Usually, you only need about 12-24 inches between plants. However, it’s wise to keep at least two to three feet above your rows if growing vertically, which means you have plants on shelves. You don’t need much space though–not necessarily. Residential growers have placed at least a couple of plants in a 2-foot by 4-foot growing area.

2. Determine the number of plants you want to grow.

Base the number of plants you want to grow on how large of a growing area you have. Again, this requires making room for space either above or around your crops.

By the way, the wattage of your lights will depend on how many plants you want to place under them. Some experienced growers also say that using a higher-wattage growing light could help make your plants grow faster. However, you also want to make sure you don’t burn your plant leaves by having the light settings turned too high.

3. Make room for the grow lights.

You know already that you need room for your seedlings to mature into full bushes. However, you also will want to make room for the grow lights. For instance, you might have to space plants further apart if you place verticle bar lights between them.

If you prefer lights that hang from the ceiling, make sure you leave enough clearance above your plants for them. Otherwise, consider installing panel lights right into your ceiling above your plants.

4. Choose types of lights according to space and function.

It’s important that your lights provide proper coverage around your plants, not just over them. Otherwise, you might produce a smaller yield than you hoped. Also, think about your growing objectives before choosing a light. Some goals might include as increasing leaf density, improved flowering rates or growing longer stems.

5. Select Settings for the Appropriate Growing Stage.

Sometimes, it’s not about the type of lamp you use or whether you decide on full-spectrum, blue, red or another color. You may need to just adjust the settings on the lights you currently have. Otherwise, invest in lights of varying spectrums for germination, sprouting, vegetative or flowering stages.

Recommended Light Spectrum for Plants By Growing Stage

Consider the types of CBD-based products you hope to produce whether for yourself or for others. Then, fine-tune your decision based on the following different specifications for either full-spectrum or broad-spectrum CBD.

Before you continue reading, keep in mind that this guide generalizes all rules concerning cannabis growing. You’ll need to also research the specific strains you want to produce. What’s more, you’ll have to decide what forms you plan to use the harvest cannabis crops in, such as stems, leaves, oils, etc.

Germination – You may just need a low level of light or total darkness for this phase. This is when the seed is still in the ground.

Sprouting – It’s wise to use the 400-500 range of blue LED when the seed has started to show above the ground. Some growers may decide to use both red and blue during the sprouting phase though. By this time, you will have your grow lights plugged in 12-18 hours per day.

Vegetative – This is the time during which the plant continues to grow. It hasn’t reached maturity yet though. Continue to use an average of 400-500 nm of blue light. About 460 nm of blue seems to increase the broadness of cannabis leaves.

Flowering – By this time, you will want to have placed a red light with a nanometer measurement of 620-720. This will increase your chance of producing the cannabis bud you may later process into CBD products.

Summary of Types of Grow Light Spectrum for Plants

Different types of lights offer a variety of grow light spectrum settings for plants. They also come in different wattages appropriate for your growing needs–and maybe your budget.

Bar Lights

Growers have used bar lights, such as the KCZZ or the FTZD LED series, for commercial growing. They have different power ranges from 480 to 1200 watts. In addition to light spectrum adjusting, they also may have dimming features for further light exposure control.

There’s also a mini-bar light series. This one starts at about 320 watts, and you might want this kind if you just have one room in a house versus a commercial growing environment. Bar lights work for vertical growing too.


You probably have to really know what you’re doing if you choose this type. Some types, including the PHDG or FDG series, are permanently mounted to the ceiling.

However, they do provide quite a few chances to change the full-spectrum light settings for plants. Wattages range from about 320 to 1200, depending on the series. There’s also the XTDG, by the way.

Grow Light Boards

Grow light boards, such as the QBLZ or the DWLZ series, also require a more permanent commitment. You can customize the QBLZ according to your LED grow light spectrum needs, and the DWLZ offers reflectivity technology. Both have external controls, which provide you more power to choose the lighting spectrums and brightnesses right for you.

Some of them run on only 110-600 watts, so they’re efficient. For the energy savings to you, it’s one of the least budget straining options we offer.


This light has ceiling mount capabilities, and it does also reach the full spectrum. Its streamlined shape fits in just about any size growing space, unlike other LED grow lights. We recommend it to people just starting out with indoor gardening.

You can use it for cannabis, vegetables, fruits or other crops in a grow room, greenhouse or other gardening environment. It doesn’t offer as many power options as large-scale lamps, but it does come in 50 or 100 watts.

The good news is, it won’t consume as much energy as some larger commercial light boards or LED beams. It ranges in color temperatures from 3000K-5000K.

UFO Light

This light also could be used by beginners. We think of it as the type of LED lamp you can incorporate into a living room if you want to grow plants there. The plants could appear decorative, and no one would be the wiser.

Of course, you’d probably feel less reluctant to keep your cannabis out in your common living areas if it’s legal in your state. In any case, it provides you with the esthetics for home growing as well as commercial production.

By the way, you can calibrate the UFO light for use during both vegetative and flowering stages. Keep that in mind before producing your next round of plants for CBD extract.

The Veg Light

True to its name, you may want a veg light like the one Boya sells. It also suits most growing environments, such as a hydroponic grow room or greenhouse. When you look on it, it does appear close to the color of daylight.

It’s also possible to produce plants on as little energy as 50 watts. This energy-efficient lighting source works well for early growing stages. Growers have also used it for “rack” or vertical growing.

Why Full-Spectrum Grow Lighting?

Perhaps if you’re reading this section, you wonder, can’t I just try an ordinary household light? Unfortunately, using a standard incandescent light bulb won’t help you much.

For starters, household bulbs that only burn at a maximum of 200 watts don’t nearly have enough lumens–not bright enough. They also don’t mimic broad daylight like high-quality LED grow lights do. The only good the ordinary household bulbs will do for you is to give you a break from eye strain if you want to turn off your LED grow lights for a while.

Why Full Spectrum and Not Green?

You don’t need to run your full spectrum grow lights 24 hours a day and seven days a week. Another option for you during the maintenance phase of your plant growing is to shut off your full-spectrum or broad-spectrum grow lights.

Then, you can run just the green lights. At this less-bright setting, you can perform your regular cultivation, watering, trimming and inspection actions and preserve your sight. At the same time, the green light seems to provide more of a benefit to your plants than a regular household bulb because it at least has moderate photosynthesis capabilities.

To explain further, you can liken it to running in place at a stoplight while you wait for it to turn green. You may feel less exerted when standing in one place but will still use up some of your body’s energy. Plants are no different. They can still benefit from any light, including green, that activates at least some of what they need to fuel their systems.

When do you use blue or red instead of full-spectrum LED?

Whatever light you use during your cannabis maintenance sessions, don’t forget to turn your full spectrum lights back on. When you do, you would resume running the 5500K-6500K color temperature for your plants during the initial growing stages. The 5500-6500K lighting is cool, blue or light. You will then later probably want to switch to a warmer light within the 2,800K-3000K range during the flowering stages.

When in Doubt, Follow Manufacturer’s Instructions

We know learning the “sweet spot” when choosing the perfect grow light spectrum for plants can be overwhelming. For that reason, the Boya grow light team always is happy to answer growing and led light spectrum questions.

If you can’t immediately reach us, follow the manufacturer’s instructions when in doubt, and watch how your plants react. Don’t worry during this process either. You’ll have plenty of time to make adjustments when setting up full-spectrum or broad-spectrum LED grow lighting.

Why Full Spectrum Lights?

We typically recommend full-spectrum lighting to most new growers, and why is that? It’s because it can help you get started in less time than if switching between multiple lights. What’s more, the types of full-spectrum LED lamps we offer typically give you all the control over your growing environment that you need.

Other Recommendations for Beginners

As a beginning grower, you might have to get used to a new indoor gardening routine. For instance, you’ll need to turn your lights off and on day and night in varying intervals. You’ll also need to spend quality time maintaining your plants.

That’s the reason we highly advise LED lamps that have timers. Programmable light spectrum functions also will save you time and frustration.

Using the programmable settings along with manufacturer recommendations is a starting point. However, we can also provide you with recommended settings for your cannabis strains.

If you haven’t noticed by now, by the way, LED grow lights are not just for growing marijuana. People use them for tomatoes, carrots, cucumbers, potatoes, celery, lettuce and more. Another area of indoor gardening that may interest you is medicinal herbs other than cannabis.

Even some ordinary kitchen spices, such as oregano, mint or basil have healing properties. These are more examples of the usages for full-spectrum lighting that might interest you.


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