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LED Lights For Cannabis — Yay Or Nay? 

Added 13 June 2022

Look at any tech niche and you will find LEDs being used everywhere — from car headlights to mobile phone displays, and from smart homes to airport runways. 

But the horticulture community is not far behind.

In recent years, LED grow lights are becoming very popular among indoor growers, including cannabis growers because they offer various benefits over other traditional light sources. However, LEDs are a tad expensive. But are they worth the investment? 

In this article, learn all about LED grow lights for cannabis and if you should consider investing in them. 

Full Spectrum LED Grow Lights

plants under LED lights

Image Credit - Diary/131653

Growers have always been using natural sunlight to grow plants and crops. Even today, many cannabis growers prefer outdoor growth for the same reason. 

This is because the sun’s light contains all the right wavelengths of light required for vigorous and healthy plant growth. However, growing outdoors may not always be practical, and you may have to invest in specific grow lights like HPS and MH to mimic the sun’s light.

Enter full-spectrum LED grow lights that are specifically designed to grow cannabis plants. They mimic the sunlight better than other light sources. Unlike traditional LED lights that use red and blue diodes to cast purple light, full-spectrum lights can cast the entire spectrum of natural light.

Benefits of LED Grow Lights

Benefits of LED Grow lights

But that’s not all. Full-spectrum LED grow lights also offer other benefits, such as the following:

  • LED lights are up to 40% more efficient than conventional light sources like HPS, HID, or CFL. This results in them saving you a lot of money on energy bills while being easy on the environment.
  • Since LED lights don’t contain any filament, gas, lead, or mercury, they are fundamentally different from other lights, which makes them very reliable in the long run.
  • Along the same lines, LED lights have a terrific lifespan, with high-quality ones lasting up to 50,000 hours!
  • LED lights also don’t heat up too much, so they don’t affect your grow room’s temperature.
  • Lastly, high-quality LED lights can be customized and tweaked as per your requirements.

Drawbacks of LED Lights

drawbacks of LED grow lights

On the other hand, LED lights have some drawbacks that can’t be ignored, such as the following:

  • High-quality LED grow lights can be expensive to purchase for hobby growers.
  • LED lights don’t produce infrared energy, which other forms of light do.
  • You get cheap LED grow lights, but they are not as efficient as other high performers. 
  • Since LED lights don’t impact the grow room’s temperature or humidity, you need to take extra precautions to ensure your room does not become too cold or humid for your plant.

Despite the drawbacks, LED lights are perhaps the best grow lights you can purchase for your cannabis plant.

Types of LED Grow Lights

The LED light industry lacks standardization, so a lot of factors dictate if the lights are right for you, like their light spread, intensity, and design. So, the next step is to understand the different types of LED grow lights and which one would work best for your setup.

Here are the common types of LED grow lights:

Quantum Board

Quantum LED

A Quantum board is a LED grow light that consists of low-wattage diodes fixed across a broad panel. Such LED lights are perfect for large or commercial setups where the light spread is important to cover all the plants under it. 

Quantum boards are also prone to heating up slightly, but reputable ones negate this heat using heatsinks, which pull the heat away from the diodes.

Spider LED 

spider LED

Another type of common LED grow light similar to quantum boards but smaller in size. These LED lights contain a main panel with arm panels stretching out like a spider — hence the name. 

Spider LED has excellent energy efficiency but is also the most expensive form of LEDs to buy. However, many growers using these lights report incredible yield and results, so the cost does seem to pay itself off.

Traditional LED Panel

traditional LED panel

You could switch to using a traditional LED panel that works as an affordable option for expensive LED boards. These are compact LED lamps that contain small to medium diodes. And since they are simple, they are cheap and easy to use. They work for basic home setups.

However, some traditional LED panels only produce purple light — a combination of blue and red. And other panels are a mix of chip-on-board and quantum board in one. But if you are looking for an affordable option, traditional panels are the best.

Chip on Board LED 

COB LED Grow light

Chip on board LED lights are relatively new, where LED chips are placed in contact with a substrate to produce a wide spectrum of light. These lights produce a high lumen density, so they are brighter than other LED lights. 

Additionally, they contain hundreds of miniature diodes connected to a single chip, so they are highly energy-efficient, too. 

Chip-on-board grow lights are known for their intense white light, which is close to the natural light of the sun. Hence, they promise optimized growth and yield.

Factors for an Ideal LED Light Setup

cannabis plants under LED grow lights

Choosing an LED light is not simple and does require some homework on your end. This is because there is no industry standard for LED lights and there are various types of LED lights. So, here is a short guide on identifying good LED lights that will work for your plant.

LED Light Spectrum

Cannabis plants have three major growth stages — seedling, vegetative, and bloom — and each stage requires a specific light spectrum. Each spectrum of light affects the plant’s growth in different ways, such as the following:

  • Ultraviolet light: UV light slows the growth of the plant and encourages oil production, and photosynthesis — as a result, it may optimize cannabinoid synthesis.
  • Blue light: Blue light spectrum affects cell expansion, leading to plants growing shorter with smaller leaves.
  • Green light: Green light is used by certain pigments within the plant to enhance CO2 usage, water absorption, and stem growth.
  • Red light: Chlorophyll absorbs a lot of red light, which improves the plant’s photosynthesis. Also, during bloom, red light triggers the plant’s flowering, so the plant can switch to bloom faster under red light.
  • Far-red light: This spectrum of light enhances cell expansion and encourages plant stretch, which is essential for vigorous growth.

This is why you need to choose an LED light that produces a wide spectrum of light and allows you to tune the spectrums as per your plant’s growth stage. Doing so can lead to your plant growing tall with bushy buds.

Light Intensity: PAR, PPF, and PPFD

Unlike HPS or HID lights, where you can measure the light produced simply by looking at the wattage, an LED light’s intensity is measured differently. This is because all LED lights are different and highly efficient, so they produce a lot more light per wattage.


Light sources produce wide spectrum ranges, but your plant requires light ranging from 400 nm to 700 nm. This range is called the photosynthetic active radiation (PAR), the spectrum that is absorbed by the plant to produce energy.

PAR is only a term that helps you determine the type and volume of light produced, but it is not a metric. 


To understand how much light an LED panel exactly produces, you need to use the metric photosynthetic photon flux (PPF), which is an accurate measurement of PAR.

PPF is a metric that measures how much PAR the light source produces within a second, measured by micromoles per second (μmol/s). Here, one micromole is equal to 602 quadrillion photons (approximately).

Now, measuring PPF is not easy — it requires a thorough understanding of maths and a lot of patience. Instead, an easy way to measure a light’s PPF is investing in a PPF meter, which can be expensive.

The easiest way is to simply choose lights from reputable manufacturers, which list the PPF on the product pages, so you can get a clear idea of the light’s efficiency. Ideally, you should look for LED lights that deliver a PPF of 2,000 to 2,900 μmol/s.


The final part of the PAR equation is photosynthetic photon flux density (PPFD), which is the measurement of how many PAR photons land on your plant. Essentially, PPFD measures the PPF levels falling on the canopy, and it is measured by micromoles per square meter per second.

You need to understand the PPFD of a grow light to understand how efficiently the LED light falls on your plant and impacts it. 

Ideally, for a small home setup, you should choose an LED light with a PPFD of:

  • 100 to 300 μmol/m2/s for the seedling stage
  • 400 to 600 μmol/m2/s for the vegetative stage
  • 800 to 1,000 μmol/m2/s for the flowering stage

Remember, these numbers are baseline values, so you still need to research a little to know what PPFD range is ideal for your plant, depending on your setup, plant strain, et al.

Also, plants have a genetic saturation point, after which the benefits of more light diminish. So, stick to the ideal numbers instead of aiming for as much light as possible. This can lead to various problems like nutrient burn, water deficiency, or light burn. 

Grow Light Distance

PPFD is crucial to understand how efficient the grow light will be for your plant, but it won’t be of any benefit if the light source is located at the wrong distance from the plant. If the light source is too close, it can cause a light burn or bleaching, and if it is too far, the plants will struggle due to a lack of light.  

So, PPFD must be taken into account along with height and coverage. Here are baseline values to determine the right growing distance for the grow lights:

Distance to Canopy

Light Intensity 



0.2 meters

50,300 lux

2,670 umol/m2/s

0.5 m2

0.5 meters

12,500 lux

2,170 umol/m2/s

1.5 m2

1 meters

3,663 lux

1,670 umol/m2/s

3 m2

1.5 meters

1,692 lux

1,170 umol/m2/s

5 m2

2 meters

955 lux

670 umol/m2/s

7.6 m2


The table above is based on 600W LED lights, but the numbers may vary depending on the type of LED you use, its light intensity, and distance from the canopy. 

Generally, LED light sources must be placed slightly closer to the plant during the vegetative and bloom stages for better light efficiency. An easy way to measure this is to place your hand under the light — if the light feels warm on your hand, it is too warm for your plant, too.

Here are the general distances for the light source from the canopy you should aim for:

  • Seedling stage: 36 to 60 inches

At this height, the light is not intense enough to dry out the seedlings, and once the seeds sprout, you can move the light closer after a few weeks.

  • Vegetative and flowering stages: 15 to 25 inches

At this height, the light source will provide intense light for photosynthesis, so your plant can grow vigorously.

Beam Angle

The beam angle is how wide your light source casts its light. The best beam angle for LED lights is 120 degrees — it is wide enough to fit multiple plants and offers adequate light penetration within the canopy.

However, if you want the light to be concentrated on a single plant, you should choose 90 or 60 degrees, which offers excellent penetration and intense light to a narrow surface area.

Purchasing the Best LED Lights

Purchasing LED lights is a different ballgame altogether. There are so many LED grow lights in the market that it can get confusing to know which one is the best for you. Plus, you can’t rely on wattage alone to determine the best grow lights. 

So, to make it easier for you, we have listed the general investment for LED lights, top brands, and a few best LED lights you can consider.

Cost of LED Lights

Whether you are growing one plant for recreation or many plants, you need to understand the initial investment. LED lights come in various cost ranges, from as cheap as Euro 100 to Euro 2,000 and more!

To know the rough investment for a grow light, you need to consider the following:

  • Number of plants you want to grow
  • Your budget
  • Its impact on your electricity bills
  • Number of lights you need
  • Return on investment 

Once you have narrowed it down, you can make an educated guess to purchase the best light. For commercial setups, an expensive light setup would benefit better than cheaper LED lights, but for a hobby grower, a simple LED lamp would work best when paired with a small pot.

Best LED Brands

Search online and you will find many LED grow light brands. Each brand offers something unique, but not all may work for you, especially the low-quality ones.

Instead, you need to choose LED lights only from reputable brands, which promise reliability and high quality. Also, reputable brands are more transparent about the design and offer an accurate insight into the light’s spectral range, lux capacity, and PPFD readings, to help you make the right decision. 

Some of the best LED light brands are Lumatek, Mars Hydro, Gavita, Vivosun, Spider Farmer, and Horticulture Lighting Group.

Best LED Grow Lights

To save you the trouble of finding the best LED light, here is a short list of some of the best LED lights of 2022.

Best Overall: Horticultural Lighting Group 650R

650R is the latest product in HLG’s product catalog and this light is perhaps the best one you can find on the market. 

650R produces an intense light of 1770 μmol/s, which is better than its predecessors, and it contains supplement lights that cast deep red and far-red light, too. Plus, the light panel is more efficient than other LED lights. 

Plus, the quality is excellent for the cost. The light contains Samsung’s LM301H full-spectrum diodes and LM351H V2 deep red diodes (660 nm). And their heat is passively managed by dedicated heat sinks.

Yes, the initial cost is expensive, but it is worth it considering its reliability, quality, and benefits. 

Cutting Edge: Scynce LED Raging Kush 2.0

If you are looking for the most high-tech LED grow light, nothing beats Raging Kush 2.0. It offers industry-leading canopy penetration with an average PPFD rating of 1,057 at a distance of 9 inches with an outskirt PPFD reading of 1,000. 

Essentially, this light throws intense light all over the canopy, not just in the focal center.

The light panel is powered by 475 watt white diodes with a temperature range of 2,700K to 6,500K, along with 175 watts of deep and far-red lights ranging from 600 nm to 730 nm. Thus, the total power draw is about 650 watts.

Perhaps the best feature of this LED grow light is its spectrum tuning that allows you to control specific wavelengths. Plus, it comes with an Android/iOS app, Theia, which allows you to wirelessly control the light’s intensity, schedule, and light spectrum. 

No Compromise Affordability: Spider Farmer SF7000

Spider Farmer is a relatively new company but it is gaining a lot of traction in the community for producing affordable yet reliable LED grow lights. 

And one of their best offerings is SF7000, which produces white light along with UV and infrared diodes. Its special feature includes a detachable driver, which reduces cooling requirements, along with a fanless design. And you can fold it in half when not using it. 

A single unit of SF7000 can cover up to 5’x5’ of grow area, but with its daisy-chain connectors, you can connect up to 15 lights, so you can expand it as per your grow room’s size without having to worry about multiple light sources. The light consumes up to 650 watts of power and is ideal for hobby growers who are looking for reliability, quality, and flexibility. 

Best Customizability: ViparSpectra Dimmable LED

Next up is the ViparSpectra Dimmable LED, which comes with a ton of customization features that help you finetune your grow light’s schedule, intensity, and spectrum. It also comes with various custom settings for each growth stage of the plant, along with a secondary optical lens.

Plus, this light is super powerful and can replace your old HPS light. So, its 1000W LED model can replace a 400W HPS light but don’t worry, it won’t actually consume 1000W, only 230W — it’s only named 1000W LED.

If you are an experienced grower who likes maximum control of your light source, this is your best option.

For Commercial Setups: Gavita Pro 1700E LED (120-277 Volt)

If you grow cannabis commercially or have a low ceiling height, you can choose this LED. This is a highly recommended grow light that is used by various commercial growers. 

Gavita Pro 1700E features one of the most efficient double-ended LED panels, which makes it super efficient for large grows. You will save a ton of money on energy bills. 

Plus, it can be kept close to the canopy, too, without worrying about a light burn, although it draws around 645 watts. And this is one of the shortest grow lights available in the market, too, at only 9.7 inches, so it can fit anywhere. 

It also comes with a Gavita controller, which allows you to control the light panels from another room and tune its light cycle, temperature, and intensity. It also features various safety features like auto-dimming, shut-off, and alerts.

Summary: LED Lights for Cannabis — Yay or Nay?

After the invention of electricity, many growers have grown indoor plants. But the artificial lights never matched the natural light from the sun. However, LED lights are changing that.

LEDs were first patented in 1961, but NASA was its first user. It performed ground-based research to not only replace lights within the spacecraft but also to grow plants in extraterrestrial environments.

After some years, growers took note of LEDs and experimented with them. But the results were subpar at best — LEDs were expensive, underpowered, and unreliable. 

But in recent years, LED lights have come far from that. Now, LED lights can compete with HPS and MH lights while being energy-efficient, unlike the latter ones. Plus, they last a long time and produce the necessary light spectrum for plants. 

Some of the recent advancements in LED grow lights include the following:

  • LED lights produce PAR light, which is best for plants
  • LED lights are fanless because they don’t heat up a lot and passive cooling can negate any heat
  • High-quality ones are also water-resistant, making them safer to be used in large, complex setups like aquaponics and making them easier to maintain
  • They are also versatile, so you can grow plants the way you like, even vertically
  • Some high-tech LED panels can work with AI and IoT to automate various processes of the cultivation process

And according to Haitz’s Law (similar to Moore’s Law), LED lights are predicted to produce 20x more light while being 10x cheaper every coming decade. So, while LED lights are giving HPS and MH lights a run for their money, they are going to improve even more in the coming years. 

So, to answer the question, LED lights are a total YAY for cannabis growers. LED lights are the future of grow lights and you can get a head start by choosing LED lights now.




I just got a Phlizon 1500W CREE COB that has an input of only up to 300W.

It's overkill as I ordered 1000W for a bargain price of £50 but got sent a larger more powerful one by mistake. So unintentionally an even better deal! Seeing that it just fits with room for ventilation, I decided to roll on with it.

My space is very tall but narrow and the area works out only to 0.164sq.m. So more than enough light now that the COB bulbs are usually kept off.

An incredible amount of light for the input and varied types of LED to tick all the boxes in the light spectrum - including IR and UV.

It gets a little warm at most but is ventilated and does well.

Very good amount of light for what I paid.

If after reading the article above you're ready to buy LED, I couldn't recommend this one more.


I recommend Panalight luminaires. Good spectrum at a good price. Regards.