The Best LED Grow Lights for Weed: Full Spectrum LED Grow Lights are Now a Must
Getting every single gram you can out of a yield is awesome!
Well, without the best LED grow lights for weed, you’re going to be leaving bud on the table—that’s a fact.
Today, I’ll show you why you should make the switch from HPS to LED, which LED grow light brands you can trust and which is the best LED grow lights on the market.
Quick Top 5 LED Grow Lights:
*Keep reading for a complete buying guide or jump straight to the top LED grow lights review!
What is an LED Grow Light?
LEDs have recently taken the cannabis gardening community by storm.
Quickly rising to the top because of they unique features the provide (more on this in just a bit).
But what even is an LED? And what makes it different from traditional grow lights?
LED stands for light emitting diodes.
And they are typically encased in a casing with a heat sink and built in fans.
Since they don’t require a ballast, you can plug them directly into the wall.
The diodes on an LED light run on average ⅓ to 1 watt of power.
Meaning your lights offer a bunch of power at a third of the energy used.
But some lights have 1W, 3W and even 5W diodes now.
LED Grow Lights vs. HPS
If you’ve been growing marijuana for a long time, then you probably know all about HPS grow lights.
After all, they were the hot new kid on the block at one point in time.
Most growers that have been resistant to the change think their yields are good enough and that more expensive LED setup costs don’t outweigh the lower monthly electric bills.
If that sounds like you, I’m glad to hear you’re at least now thinking about giving LEDs a shot.
The reasons we think LED win out over HPS every time are simple:
Dealing with temperatures that are too high is a big enough problem on its own (especially if you live closer to the equator).
Your lights shouldn’t add to the fire.
The temperature difference between LED lights and HPS lights is almost a biggest enough selling point on its own.
Plus, having cooler lights saves you money by not having to buy extra exhaust fans.
Now, if you grow in a much cooler climate you might consider growing with HPS lights to help keep your grow room warm enough to grow cannabis, but this is rare.
- Light Intensity
When it comes to light intensity HPS and LED are pretty damn close.
But, HPS definitely has the upper hand.
Keep in mind , though, it's not lumens (light intensity) that plants need but rather the right wavelengths.
What’s our goal when growing our own cannabis?
Fat amounts of bud!
So, how do HPS and LED lights compare when it comes to yield?
On average, you’ll get around .5 grams per watt with an HPS light. Full spectrum LED grow lights, however, give you anywhere from 1 gram to 1.5 grams per watt.
If you can 3x your yield just by investing in new lights, it seems like a pretty easy answer to me!
This is another area where LED grow lights just absolutely crush it.
With an HPS light you can expect about 10,000 hours (sounds like a lot, right?).
Well, with an LED 50,000 is the low end with some lasting all the way up to 100,000 hours!
- Distance from Plants
Because of the massive amounts of heat exuded by HPS lights, you don’t have as much freedom as to where you can place your lights.
With LED lights, however, you can get them closer to your plants making it easier for them to absorb the light.
- The Spectrum of Light
LED lights let you custom tailor the wavelength you’re giving your plants, and most come preset for the perfect type of light your plants need during the vegetative and flowering cycles.
HPS lights, on the other hand, emit the entire wavelength, so a lot of the light goes unused by your plants.
More Benefits of Using LED Grow Lights
We’ve already touched on quite a few benefits of using LED lights, and we’ll dive deep into a lot more later on.
Most of us don’t have even a full room to devote to growing our marijuana.
No, most of us are either closet growers or we're lucky enough to have an awesome grow tent or a grow cabinet.
Whatever you may be growing in, LED's will be your best choice because they are:
- Smaller and easier to install: LED lights are plug and grow and use chips to convert energy into light. So, you don’t need extra equipment just to run your lights.
- Easier to plan ventilation with: You don’t have to worry about running extra ventilation just to remove the heat caused by your lights.
- Give you control over the spectrum: You control the wavelengths you provide your plants allowing you to give them exactly what they need during both stages of growth instead of the one size fits all mentality of HPS, MH or fluorescent lights.
And that’s not even considering the energy savings!
How to Choose an LED Grow Light
When it comes to outfitting your garden, there are so many options with every single thing you need to buy, and it’s no different for grow lights.
But there are a few specific things you should look for when making your decision.
After all, the lights can end up being the most expensive part of your garden, and you don't want to make an investment that you end up regretting!
The spectrum of your light needs to be at the front and center of your decision.
Grow lights for cannabis need to include red and blue wavelengths and also ultraviolet and infrared.
It’s also crucial the light be good for all stages of growth!
Some aren’t, so you need to pay attention to the spectrum they say the light offers.
For instance, if your light just runs heavy on red, it will waste a lot of energy of wavelengths that won't be absorbed by the plant during the vegetative stage.
Energy saving and great power efficient
When it comes to LED lights, you want them to produce more light while using less electricity.
Pay attention to the ratio of equivalent wattage and actual power drawn wattage.
As mentioned earlier, one of the biggest advantages of a LED is the lifespan, right?
If you have the option of one that will last 50,000 hours vs. 100,000 hours you need to consider if the extra cost up front is worth having a longer lasting light.
Low Levels of Heat Output
Not only is low heat output good for your cannabis but it also adds to the lights durability.
You want the light to offer some built in fans to help cool the lights down even more.
Good LED lights have aluminum heat sinks built into the system to keep them cool.
Constant Current Driver Circuit
LED circuit drivers should constantly be supplying a direct current of energy and should regulate the intensity in response to any changes in temperature.
Should You Choose a Full-spectrum LED?
To understand what a full-spectrum LED grow light is you need to know a little about the spectrum they are referring to.
For starters, let’s talk about photosynthetically active radiation (PAR).
Specifically, PAR is a spectral light range of 400-700 nanometers and is what most plants use during photosynthesis.
You can use a PAR meter to measure the intensity of your lights within the spectrum.
All of the light wavelengths that plants love are found on this spectrum—blue, red, infrared and ultraviolet.
So, to be honest, the term “full-spectrum” does not mean the light produces every wavelength imaginable, but rather that it’s producing the wavelengths of the PAR spectrum.
You must also keep in mind that grow light companies do not have to get their lights tested and approved to be called full-spectrum, so you can only trust the term as far as you can trust the company behind the light.
So, do you need a full-spectrum light?
Your plants will benefit greatly from a light that produces all of the wavelengths of the PAR spectrum at a strong and continuous rate, so yes!
That’s not to say plants don’t use wavelengths outside of the PAR spectrum.
But they are either too intense or too weak to be of any use during photosynthesis.
Also, photons in the PAR range contain the perfect amount of energy for the plant's electrons without causing damage.
How do Plants Absorb Light?
Stay with me here.
We are almost through the very science-intensive portion of this guide!
To absorb light, plants use pigments.
The most abundant one they have is chlorophyll which they use to capture both blue and red light.
Other pigments that absorb light are carotenes and xanthophylls that work to harvest various wavelengths before passing it over to photosynthesis.
You should also know that plants absorb green light deeper into their tissue that any other color.
That’s why green light can make photosynthesis run more efficiently in a plant.
This happens because the chloroplasts that contain chlorophyll end up becoming saturated allowing green to pass deeper into the plant tissue where it’s bounced around until it’s absorbed by an unsaturated chloroplast or another pigment.
How Many Watts Do You Need for the Best Yield?
Now I know that might have seemed a little heavy on the science, but it’s important for you to understand every aspect of your grow room fully.
And since the lights are just about the single most important factor, you should spend time studying them.
But now on to the stuff that moves the needle:
How many watts you need per square foot with an LED.
When it comes to LED lights, it’s not the watts are important.
Using watts to determine how much lighting is sufficient for a given area is a legacy system built upon HPS lights.
Still, it’s the most used terminology even with the rise of LEDs, so we’ll use it.
First, you need to know that when a LED light is advertised as 300 watts, it’s referring to its HPS and metal halide wattage equivalent and that it's only drawing in around 135 watts of power.
The number you need to know if a light will work for your grow tent is the true power and not the equivalent.
On average, with LED lights, you need 32 watts per square feet of actual draw power to grow cannabis.
This is the wattage needed during flowering, while in the vegetative stage you might consider running around 50% of this.
You can use this calculator to see how many watts you need quickly:
Tips to Avoid Problems with LEDs
There is some subtle differences between growing with old school lights and LED lights.
The low heat output might trick you into thinking you can put the light practically sitting on the plant and call it a day, but be warned.
While there isn’t an exact science to it, LED grow lights need to be placed around 12-18” from the top of your plants.
If you let the lights stay too close to the plants, not only will it stunt their growth, but LED lights can cause your cannabis leaves to turn discolored and closely resemble a nutrient deficiency.
Obviously, this can be a problem if you start messing with the nutrients when the problem is nowhere near the cannabis soil.
If you spot discoloration, pay attention to see if it’s near the lights or not.
If it is, you probably found your culprit and then move your lights back to prevent further light burn.
LED lights that are too close can also bleach the top of your buds.
This is especially common during flowering after the plants have been under the LED for months.
You also need to keep an eye out for colas that are standing way above your other plants.
If you do have one or two stray tall colas, you might consider tying them down to make them grow more horizontally, so they don’t get too close to your light.
The distance your plants need from the light is also determined by the LED lights “chip.”
For instance, if your light has 1W chips your plant will thrive at 12” away.
While with a 3W chip or bigger the plant will do better at 18”+.
Don’t be afraid to ask the light manufacturer the recommended distance from the light.
You don’t have to say your growing weed!
Just say you’re growing high crop plants and they’ll be able to help you.
What are the Best Brands?
If you’re still with me, I know you’re serious about finding the perfect LED lights for your grow room.
And, even though I am about to tell you which ten I think are the best available, you might want to know the reputable brands, and then you decide on your own after more research.
Plus, will all brands even work well for growing cannabis?
That’s a good question! But, I don’t know.
I do know this, though.
Here are a few of the top LED light brands that always put out quality grow lights:
Now, I’m sure you’ll notice that we don’t include any Black Dog or Kind LED grow lights on our list of the best.
And, it’s not because they aren’t great, it’s just at around $1500 for a light it just isn’t what a casual cannabis grower needs.
When considering the LED grow lights that were going to make our list we factored in price, spectrum, wattage, heat and what other cannabis growers are saying about them.
So, while we do recommend Black Dog and Kind lights, if you’re just growing for personal use, you can save a ton of money going with a brand like Vipar Spectra or Galaxy Hydro.
The Best LED Grow Lights for Weed
- Grow Space Coverage: 3’x3’ - 4’x4’
- Actual Power Draw: 276W
- How Far to Keep from Plants: 14-24”
- Watt Sizes Available: 600W, 1200W
When it comes to growing good bud, you need lights like Viparspectras.
This lamp is available in both 600W and 1200W versions making it work for most anyone's situation.
The 600W LED light pulls 276W and is the perfect amount of light for a 3’x3’ grow tent—which you can fit about four good sized plants in yielding up to 1.5 grams per watt each!
Basically, this light has your plants covered.
It’s full-spectrum, hitting all of the wavelengths in PAR, and with its huge cooling fans you never have to worry about overheating.
It features 130 5W Bridgelux/Epileds LED Chips that will last you over 100,000 hours—that’s a lot of harvests!
Not only does this kit come with a chain to hang it up, but it also comes with bloom and veg switches.
This means you can just run the blue lights during vegetation and red lights as soon as it’s starting to bud.
These lights will help your plants develop strong stems, but also nice, thick buds.
It’s tough to find a negative thing to say about this LED grow light!
- Grow Space Coverage: 2’x2’-3’x3’
- Actual Power Draw: 135W
- How Far to Keep from Plants: 12-24”
- Watt Sizes Available: 300W
If you’re rocking a smaller garden, the Galaxyhydro LED lights will grow your plants up to be healthy and your nugs to be dense.
It pulls around 135W while being equivalent to a 250W HPS and a 400 MH.
This model even comes with UV and IR lights that help both promote cell division (IR) and kill bacteria (UV).
As of right now, they don’t offer a version with more wattage, so if you need a light to cover more than a 3’x3’ grow room, then you’ll have to pick up a couple more supplemental lights.
The quality of this light is exceptional, though.
And it runs at the perfect spectrum for growing quality cannabis.
It’s built with 100 3W Epileds chips which are quality chips and all together it produces around 7000 lumens.
But remember, with LED lights lumens aren’t what’s important.
It also has two built in fans that help keep your grow room cool, and they're quiet—so don’t worry about them running loud.
I just wish that this lamp had an on and off switch.
It can be a hassle, but with how much bang you’re getting for your buck it can be overlooked
- Grow Space Coverage: 5x2 - 6x3.75
- Actual Power Draw: 184w Veg / 368w Bloom
- How Far to Keep from Plants: 18”
- Watt Sizes Available: 150W, 300W, 450W, 600W, 900W, 1200W
The first thing you’ll notice about this light is how dang bright it is!
They claim it’s 2x-3x the intensity of any other LED lights, and I just might have to give it to them.
The P600, which is equivalent to an 800W HPS, is outfitted with 200 3W chips—all made in the US.
Its light wavelengths include 12 bands all the way from UV to IR, and its four high-speed fans are quiet.
Like most of the good LEDs, it has switches to either run veg or bloom or both at the same time.
Now, here’s the kicker:
It's by far the most expensive light on our list.
While the Advanced Platinum Series could very well be the highest quality light here, you can get near the same quality for a fraction of the cost.
I don’t normally bring up the warranty, but these guys back their lights so much they offer a 5-year warranty with tech support seven days a week!
- Grow Space Coverage: 3.4 x 3.8 ft
- Actual Power Draw: 185W
- How Far to Keep from Plants: 18-24”
- Watt Sizes Available: 600W, 800W, 1000W, 1200W
King Plus brings an interesting and unique approach to the efficiency of LED lights.
Instead of housing a bunch of 3W or 5W chips, it uses 10W double chips that help not only save energy (think cheaper electricity bill) but also a longer lifespan.
While it is a full-spectrum light, it doesn’t offer veg and bloom switch like we like to see in LED lights.
What it also does better than most is keep cool.
They use wider venting holes for more efficient heat dissipation.
This light is bright too! Puts out about 16,000 lumens so be sure not to look right at it!
The light goes straight down, and so make sure your garden area is well reflected or keep your plants directly under the lamp.
- Grow Space Coverage: 4x4
- Actual Power Draw: 252W
- How Far to Keep from Plants: 18-24”
- Watt Sizes Available: 300W, 600W
This is a 600W light by Roleadro, and it rounds out our top 5.
It's full-spectrum hits all the PAR wavelengths your plants need to grow big and fat.
Plus, it has the added functionality of IR and UV.
Comes with a daisy-chain to hang it up, and since LED lights don’t need a ballast, it’s plug and grow.
It produces light by calling on the power of 120 5W Epiled chips creating a bright light that produces oodles of lumens.
It has fans pretty much cover every bit of surface that doesn't house the lights, keeping it cool.
My favorite part of this lamp is how easy it is to string a bunch of them together.
Thanks to the double female outlets on each unit you can run multiple lights while only using one outlet.
One thing I love about LED grow lights that have a white tint is it makes it easier to look for abnormalities on the leaves with the lights on.
You will probably want to upgrade the hanging system, though.
It’s set up to hang from a single point making it hard to level multiple lights out, and I just personally prefer a four-point hanging system.
- Grow Space Coverage: 3x3
- Actual Power Draw: 285W
- How Far to Keep from Plants: 18-24”
- Watt Sizes Available: 600W, 1200W
Another awesome light from Viparspectra!
They really are one of the best in the game when it comes to affordable grow lights.
This light keeps up with a 600W HPS while only running at around 285W—It doesn't cut back on energy use as much as some of the other lights on this list.
It’s full spectrum lights are enough to grow big buds in a 3x3 area, but you can stretch it to 4x4 if you need to—especially with a couple of supplemental fluorescents.
What stands out about this grow light is the souped up fans.
And I do mean souped up!
Not only are they big and quiet, but the unique frontal fan design helps keep this light cooler than most.
My favorite part though is the adjustable hanging kit, which allows you to adjust the height as your plants grow easily.
Plus, it has three switches allow you turn on the white, red and blue lights separately.
- Grow Space Coverage: 5x4
- Actual Power Draw: 185W
- How Far to Keep from Plants: 18”
- Watt Sizes Available: 600W, 1000W, 2000W
If you’re a shoestring budget cannabis gardener, you can’t get much better than a Bestva light.
Having one of the best watts per dollar ratios on our list, it’s a big favorite of the budget conscientious gardener.
Built with 10W dual chips, these lights run super efficient and last quite a long time—100,000 hours.
The “1000W” model draws 185 watts and replaces a 600W HPS light, so I’m not sure why they call it their 1000W model.
Regardless, we all know that with LED lights it’s the actual equivalent and the spectrum that matter.
So how does the spectrum stack up?
It comes in at 380-780 nm which is just inside PAR.
The big issue I have with this light is that you need to turn it off for 30 minutes every eight hours.
That is if you don’t want to worry about it overheating causing a shortened life span.
While it’s not a big deal in flowering, in the veg stage, it can be a little tricky to manage, and most will probably opt to look past this manufacturer's suggestion.
- Grow Space Coverage: 3.5x4
- Actual Power Draw: 130W
- How Far to Keep from Plants: 18-24”
- Watt Sizes Available: 600W, 1000W, 1200W
Available in three different sizes, this ColoFocus light is a great addition to any grow room.
Another one that is rocking 10W double chips and UV plus IR lights.
Its spectrum falls into PAR with 90% of the wavelengths being used by the plants.
It has two independent fans helping to keep the system cool.
There isn’t any way to switch between veg and bloom lights which is a huge knock against this light.
But, if you want a light that will create dense flowers, you’ll be thoroughly pleased.
- Grow Space Coverage: 4x 4.5
- Actual Power Draw: 270W
- How Far to Keep from Plants: 18-20”
- Watt Sizes Available: 1500W, 1800W, 2000W, 2400W
Morsen is a quality brand that makes a pretty damn good light.
Only available in high wattages (1500w-2400W), these lights are perfect for a closest, but they can also handle a larger grow tent.
It has multiple fans that help to extend its life.
It uses 10W chips and can switch between spectrums depending on the stage of growth your cannabis is in.
I will say, compared to other LED grow lights it runs a little hot, but still way less then it's HPS counterpart.
The Best LED Grow Light for Seedlings
When growing seedlings, you don’t need much light at all!
In fact, too much can easily burn or wilt your tiny cannabis plants.
What you need is the perfect spectrum and at a nominal amount.
And you don’t need to break the bank for your seedlings light either.
That’s where this 45W Roleadro panel comes in.
Putting out just enough light for a few trays of seedlings or even your clones, this is the perfect light to get your marijuana growing on the right root.
I hope you learned something in this huge guide on the best LED grow lights for weed.
If you have any other questions regarding full spectrum LED grow lights, please don’t hesitate to ask.
Did you end up getting any of the lights I recommended?
Let me know in the comments below!
Last update on 2018-08-19 / Affiliate links / Images from Amazon Product Advertising API