When creating an indoor setup for growing marijuana, one of the most important decisions is what kind of lights to use. In this article, we’ll cover a few of the different options and details about LED lights and growing marijuana indoors.
- The advantages and disadvantages of using LED lights
- LED lights vs. other lights
- How do LED lights work?
- The LED lens
- High powered LEDs (HPLEDs) and low powered LEDs
- Making high-intensity white LEDs (WLEDs)
- Differences in price and quality
- Common problems with LEDs and how to avoid them
- FAQ About LED Grow Lights
LED grow lights have not always been popular with marijuana growers. However, technology has improved, and so have LED lighting systems. Although they would not have been a reasonable choice for marijuana growers five or ten years ago, they are becoming more popular every day. We can now find LED lights not only in the marijuana grow room, but also in cars, offices, and homes.
Many people swear by LEDs instead of HID setups, asserting that they are a far superior and more energy conscious option. If you go with LEDs, you will save energy, money, and management time.
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The advantages and disadvantages of using LED lights
While LEDs sure sound amazing at first, this does not necessarily mean that they are the right light choice for you and your indoor marijuana grow setup. Let’s go over some of the major pros and cons that come with using LED lights.
First and foremost, the energy savings are enormous. If you compare using an LED light for the same purposes as you would an HID light, using the LED light will save you about 40% of the energy consumption. They also last a lot longer. You can expect between 50,000 and 60,000 hours of working use of an LED light, compared to between 2,000 and 3,000 hours with an HID light. This is because LED lights don’t have a filament to burn.
LED lights take up less space, emit light faster, and are more durable and shock-resistant than HID lights. They also have a much lower heat output, therefore lowering the need to keep your grow room cool. This reduces the risk of fire significantly. HID lights will become very hot, but good LED lights feel cool when you touch them, even after running for several hours.
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LED lights focus using the lenses, which means there is less of a need for reflectors like HID lights, which disperse the light without focusing and, therefore, need an external means of focusing. HID lights need approximately 100 to 150 Watts of more power than LED lights since there is power management built into the LED lights. HID lamps require external ballasts and, therefore, add extra watts of consumption.
LED lights turn instantly on and off, unlike HID lamps, which need to warm up before being fully lit. LED lights can even be dimmed quite easily. Classified as “Class 1 LED product,” LEDs are considered a safer lighting option. This is because they don’t have mercury like some other lights, such as compact fluorescent bulbs (CFLs).
The efficiency of LEDs is particularly noticeable when compared to CFLs. You can expect to save about 50% of your energy bill when you choose an LED over a CFL.
When using LED lights, precise power (current) management is necessary. Additionally, LED lights have higher upfront costs. That being said, they are less expensive over longer periods of time. LED lights particularly need more specific current and heat management than do HID lights, when they are powerful lights to be used to light entire large areas.
LED lights vs. other lights
One of the biggest questions to consider is whether you should choose an LED light setup or one of the other options for an indoor grow setup. How do LED lights measure up to other types of grow lights? Let’s look at the differences in lighting.
LEDs vs. CFLs
The most common light that has been traditionally used to grow marijuana is the CFL. CFLs are tried and true, having been used for generations, causing many growers choose to go with them, despite the fact that LEDs are often hailed as a more efficient technology. For people who have properly done their research on lighting systems, LEDs are almost always the winner. While CFLs needed to be adjusted pretty much on a daily basis, LED lights do not need this frequent maintenance.
LED lights also do not release the large amount of heat that CFLs do. They are well-equipped with cooling systems such as fans or heatsinks as well, which allows for an easier time of keeping the grow room at a temperature that isn’t too high (for the plants as well as the grower).
That all being said, there are some situations where using CFL lights makes more sense. One such situation is if your indoor growing area is on the shorter side. This is simply because LED lights need to be kept further away from the plants than CFLs do. Generally speaking, LED lights should be between twelve and eighteen inches above the canopy of your plants (although this should be cross-checked with the specific manufacturer) while CFLs just need a minimum of a few inches.
LEDs vs. MH/HPS
While many growers choose either LEDs or MH/HPS lights, the fact is that combining the two might provide the most advantageous setup you can find. Without the scientific evidence to prove it, many growers will swear that HPS lights turn out much prettier buds while LEDs get them to be denser and more potent. Therefore, using both should give you the best of both worlds.
Many growers have specific requirements for their situation that make either LED or MH/HPS lighting a more logical choice. For instance, if you are trying to keep the upfront costs of your grow room as low as possible, using an HPS grow light during the flowering phase makes the most sense. If you compare electricity used to the resulting yield, MH/HPS lights will give you the best bang for your buck. Electricity aside, they also simply cost much less than LED lights.
There is also a higher degree of variability with LED lights. If you buy LED lights, you must always check the manufacturer’s information to know what “rules” to follow. MH/HPS lights, on the other hand, are highly standardized and the models all fall into the same category of rules for the most part.
Many assert that LED lights get a better quality bud than MH/HPS lights, however. More trichomes, greater potency, and a stronger natural taste and smell are all associated with using LED lights.
How do LED lights work?
Most simply, LED lights use a current passing through a semiconductor to produce light. The energy (in the form of light) is released from moving electrons inside the semiconductor. They used to only be available in the red, but now they are available in any color, ranging from ultraviolet to infrared wavelengths.
The invention of LED lights is credited to H. J. Round, a British man from Marconi Labs who, in 1907, was the first to experiment with, and observe electroluminescence. Fast forward twenty years to when the actual invention of the first LED light finally came about. But even the Russian inventor, Oldeg Vladimirovich Losev, couldn’t find a practical way to use the light. It wasn’t until 1955 that Rubin Braunstein observed semiconductor alloys, and six years later, Texas Instruments took over with a patent.
LED colors are made via electronic action occurring at the p-n junction. This junction is where the n-type and p-type semiconductor materials emit energy, resulting in the color of the light. This light wasn’t even observed until 1962, when Nick Holonyak, Jr., working with General Electric, witnessed the red LED light. His graduate student, named Craford, then invented the yellow LEDs and also made the reds and orange LEDs ten times as bright by the year 1972. Blue and white followed similar development, via other experimenters and companies.
3 band, 5 band, 11 band, and full spectrum LEDs
The different colors of LED lights actually stimulate and trigger different types of growth in marijuana plants, for example:
- LED lights within the blue spectrum spur vegetative growth.
- LED lights within the yellow, amber, red, and far-red spectrums spur pre-flowering and flowering stages, which includes reproductive growth.
Generally speaking, using lights to grow marijuana indoors can be successfully done from sprout to harvest by using between 420 and 730 nanometers (nm). Therefore, if you want to grow marijuana that ends up with a successful yield, you will need LED lights that include and use the full spectrum.
If you choose an LED light that has only red or blue lights, it simply will not get your plants to grow to their full potential, like a white LED light (also known as a full spectrum LED light) would. White LED lights contain closer to the full spectrum, making them more similar to the sun than single color LED lights. Even red and blue lights together will not do it. You need white LED lights.
So what exactly are the other types of LED lights, such as the 3, 5, 6, 11, or 12 band LEDs that are advertised? These LEDs have a spectrum that includes those gaps. They might be 440, 470, 525, 640, 660, or 740 nanometers. These lights do not offer the same full spectrum that a proper white LED light would provide.
Instead of white LED lights, you will often find many different diodes on store shelves, or online. Some claim to be able to match the PAR spectrum more accurately than a white LED. When you shop for an LED light for your marijuana plants, you should be aware of the exact spectrum that it covers, and know whether it coincides with the PAR spectrum as closely as possible.
The fact about the PAR spectrum is that the better an LED light matches it, the more efficient the light will be. Less light will be wasted since there will be a higher ratio of usable light for your marijuana plants. This helps marijuana growers save on their power bill while simultaneously spurring better growth in your plants. There is also less heat loss, which means cooling your grow room is much easier with LED lights.
Thermal management of LED grow lights
LEDs don’t get as hot as other types of lights, and they are also far more efficient than other lights. This efficiency is because they don’t burn filament. The vast majority (95%) of an HID lamp’s energy is actually wasted as heat or radiation, therefore reducing its efficiency significantly. Since LEDs are generally cooler in temperature, they waste far less energy as heat.
When using LEDs or HIDs as grow lights, it’s important to take these heat differences into account. HIDs need to be situated several feet above the tops of your marijuana plants, for example, while LEDs can be kept really close to them (between one foot and 18 inches).
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This does not mean, however, that LEDs have absolutely no heat issues associated with them. While they don’t feel warm because they aren’t emitting infrared radiation, the high powered LEDs are actually less efficient and, therefore, waste more heat than low powered ones.
If you have high-quality LEDs, they should have heat sinks that keep the heat under control. These heat sinks allow for the dissipation of unwanted heat. Any LED lights that are below 700 watts should use heat sinks to cool them. For high powered LED lights, heat sinks should include aluminum, copper, thermoplastics, or even graphite (for the most expensive option). A large surface area is required for the heat sinks to work efficiently, so don’t be surprised by odd fin shapes designed into some of the more expensive lights.
Because of the requirement for a large surface area, heat sinks will not be as practical of an option for the largest LED lights on the market. Therefore, some of these larger lights use passive heat sinks combined with fans to keep cool, although the best designs don’t need a fan at all because the sinks work well enough.
Whatever type of cooling system your LED light has, make sure it is high in quality. Low-quality cooling systems will cause your LED lights to deteriorate fast, so it’s better to pay the higher upfront costs to get your money’s worth in the long run.
The LED lens
One of the best qualities of an LED light is the fact that external reflectors are not needed to focus the light on one area efficiently, unlike HID lights. Instead of requiring these reflectors, LEDs use a lens to focus their lights onto a smaller area in full force. The plastic shell holds together the entire LED system: the “chip” that sits in the potting, which also serves as the lens for your LED, boosting the light out of the semiconductor. Depending on the quality of the way the chip was “potted,” the light output can vary considerably between cheap and very expensive options.
Remember, the actual extraction of this light is equally important to the type materials being used for the semiconductor. This is why sometimes people prefer to purchase reflectors even though they have LED lights. Reflectors don’t need to be complex to be effective. If you are getting a lens instead, go for a Total Internal Reflective (TIR) lens because it is the most accurate and complete.
The best LED lens for directing light right onto the plants is one with a 90-degree angle, although some products are 120-degree angles. The typical output of an LED light is around 160 degrees. If you choose a lens that is too wide, it will cover a greater area but will be less efficient because less light energy will be hitting your plants, and instead, will just be wasted. Don’t buy an LED light without a lens.
High powered LEDs (HPLEDs) and low powered LEDs
Regular LEDs use 30-60 milliwatts (mW), but higher powered LEDs use around 500 mW, or even more. The first 1-Watt LED light came out in 1999, but many people don’t understand the difference between a 1-Watt LED and a 3-Watt LED. To put it simply, the 3-Watt LED can run at 1 Watt, but the 1-Watt LED cannot run at more than 1 Watt because that is its limit. In other words, these names refer to the highest possible potential power output from the light.
Making high-intensity white LEDs (WLEDs)
Since you already know that white LEDs are the best choice for growing your marijuana plants, let’s look at the different ways they are made. There are two primary methods used to produce high-intensity white LED lights.
The first method involves using one LED that just gives off three colors of light: red, green, and blue. These lights get mixed together to form one perfect white light. These lights are considered multi-colored white LEDs, or RGB LEDs, and are the most effective type of WLEDs.
The second method requires you to use a phosphor-based semiconductor material that converts one color (blue or UV) into the full spectrum white light. These WLEDs are called phosphorus based white LEDs, and they are cheaper to produce (and buy) than the above version.
Another type of WLED does exist, but it is hardly worth mentioning because it has barely been developed. It uses zinc selenide (ZnSE).
Differences in price and quality
To start with, it’s a given fact that almost every LED grow light that you will find in stores, even ones with American designs, will be produced in China. At a minimum, most or all of the different components will come from China. There is a difference in quality between the low, middle, and high prices LED lights, we’ll explain those differences to help you choose the best lights for your grow room setup and budget.
Generally speaking, LED lights in the low price range have a poor spectrum and are low in quality. They are generally UFO LEDs found online, often misrepresented as “full spectrum” LEDs that can easily be recognized by what they actually are due to the fact that they are clearly large blue and red LED lights in a cheaply made plastic shell.
Because these are lower in quality and spectrum, they will hurt the growth and yield of your marijuana plants. Simply put, these LED lights are not recommended over HPS or MH system lights, making it not worth the money at all.
These LED lights will be more reasonable in their quality. They will have a better shell, come with a built-in fan, and will come from higher quality brand names that should be familiar although they still will not have the full spectrum that their more expensive counterparts will. More likely is that they are models with either 6, 8, 11, or 12 bands. The primary function of these bands is that they will cover the entire PAR range, but not thoroughly; there will be some gaps missing throughout. This means that, although they are better than the lower quality version, they are not as close to the sun’s spectrum as you can get with LED lights.
These are the types of LED lights that are going to get you the best results in terms of marijuana plant yield. They don’t need a fan to stay cool, they are built with the best materials, and they incorporate the entire spectrum, getting as close to the PAR (and, therefore, are the most sun-like) as possible. These models should cover a range from 420 to 750 nanometers. Sometimes they will appear dim or dead to people because of the far-red part of the spectrum, which is 710 to 850 nanometers and is hard to see with many people’s eyes.
The highest quality LED lights will be from companies such as Cree, Bridgelux, or Epistar. The lights have the highest thermal engineering, allowing them to operate without a fan and still stay cool. You can rest assured that plants growing under these lights will reach their maximum yield potential, helping you end the season with a fantastic product. Although the costs are higher for these LED lights, the results are equivocal, making it well worth the extra spending.
Reputable LED brands
Whatever type of LED light you buy, make sure you choose one from a reputable source. The problem with there being so many options these days is that plenty of those options are sub-par, meaning consumers need to do their research before buying. Ask in-depth questions about the light intensity and the spectrum, and check for the most highly recommended products around.
We can recommend a few brands although there are certainly more brands out there that have similar high-quality LED lights. Some of the best brands for LEDs that grow marijuana include Advanced Platinum Grow Lights, GalaxyHydro LED Grow Lights, Pro-Glow LED Grow Lights, Kind LED Grow Lights, and Advance Spectrum LED Grow Lights. Be sure to do your own research into these brands and others to find the brand that is right for you.
- Advanced platinum grow lights:
These lights are a fairly recent development on the market, but this in no way means they are lower quality than other, older brands. These lights are usually a reasonable price, come with good customer service, and even have a trusted warranty that lasts for 5 years on all of their models. Their models include the Advanced Platinum P150, P300, P450, and the P600. All of these models work best in different grow room setups, so be sure to read into it and ask questions about specific models if necessary.
- GalaxyHydro LED grow lights:
Like the Advanced Platinum Grow Lights, GalaxyHydro is also a relatively new brand. The results from their lights are consistently positive, however, and we can recommend the GalaxyHydro 300W LED Panel, the GalaxyHydro “Roleadro” COB 200W, 270W, or 400W LED Grow Light, and the 300W “Full Spectrum” LED Grow Light.
- Pro-Glow LED grow lights:
These lights are considered some of the most expensive, but also the highest quality ones on the market. You can find all sorts of research and records online showing their positive results, so if you have the money and really want to do it right, the Pro-Glow lights are worth it. The models include the PG-180 LED Grow Light, the PG-400, the PG-X5-300, the PG-400X, and the PG-750.
- Kind LED grow lights:
These LEDs have skyrocketed in popularity in recent months among the marijuana-growing crowd. They provide numerous available models, but so far the only one used and recommended for marijuana plants is the K3 L600 model.
- Advance Spectrum LED grow lights:
Not quite as much is known about this company at this point, but so far the experiences with them have sounded positive. In particular, the S540 is recommended for marijuana growers.
Common problems with LEDs and how to avoid them
If you’re looking for an everyday, “standard” type of grow light, then LEDs may not be for you. They require a certain amount of research and patience, and they achieve different results than other types of grow lights. In order to avoid some of the common problems that occur with new LED growers, let’s look at some important facts and common problems with LED lights.
They change the appearance of your plants
Many growers who are newly using LED lights begin to panic when they see that their marijuana plants apparently have nutrient deficiencies because of some strange discoloration taking place. Before you start testing the pH levels and loading your soil with extra nutrients, however, consider the fact that it might simply be from using LED lights – and it is not necessarily a bad thing.
It is most common to see such discoloration during your plants’ flowering stage, particularly when they are reaching the end of it. The leaves will start appearing discolored, but as long as the lights are far enough away, the leaves aren’t actually falling off of the plant, and the buds are still healthy as ever, there is nothing wrong with your plant at all.
Distances can vary
Because LED lights are not as standardized as other types of lights, it is crucial that you check the manufacturer’s instructions for how far away from your plants your new lights should be. This distance varies according to the bulb size as well as the type of lens, so don’t start using it until you feel confident that you fully understand what should be done with your specific LED lights.
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Generally speaking, smaller LEDs that have 1W chips should be a minimum of one foot away. The majority of LED lights with chips that are 3W or larger, however, should be at least 1.5 feet away. Otherwise, you could give your plants light burn. Remember that you can always ask the manufacturer for recommendations yourself. If your plants are starting to appear burnt on just their top part, you should probably try moving your LEDs further away.
HPS lights get a higher yield
While this statement is probably true, that does not necessarily mean that you will get a better yield with HPS lighting. LED lights may achieve a lower yield than HPS lights, but it is well known that buds given light from LEDs will be stickier, stronger, and have a more intense aroma. Remember, more is not always better, especially when you are growing something that will be consumed or smoked later.
Thanks for reading. Please leave comments or questions below and don’t forget to download my free grow bible.
FAQ About LED Grow Lights
Your plants won’t grow as healthy or efficiently with any LED light, since only LED grow lights provide the full spectrum that the plants need to reach their full potential.
LED grow lights are popular due to them being energy-efficient, durable, and providing the light spectrums that your plants may need.
LED grow lights are generally placed about 16 to 36 inches away from the plants.
The founder of I Love Growing Marijuana, Robert Bergman, is a marijuana growing expert that enjoys sharing his knowledge with the world. He combines years of experience, ranging from small-scale grows to massive operations, with a passion for growing. His articles include tutorials on growing... [read more]