Knowing nothing at all about LED grow lights, I simply started reading LED grow lights reviews on Amazon. It seemed like a great place to start, due to the interaction between folks with questions, and those who have answers. In the reviews-sections, you’ll usually find some kind souls who took the time to put their knowledge into writing. Or other customers have already asked things that I also find myself wondering about. Some reviews are incredibly extensive and contain good information for a layperson to start with.

I’ve learned a few basic things about LED lights, how they work, what to look for, how the leading brands compare to each other, or how to build the best set-up. These are my takeaways after reading a very large amount of LED grow lights reviews.

1. More is more.

Getting more of the smaller panels versus a higher priced single large panel could be a good idea. This allows much better light coverage for your plants and will create that yield you are looking for.
If you’re wondering how many lights to get to cover for example an 8×4 area, two of the higher strength (1200W) could do, when looking purely at the numbers. However, you may be better off with several of the smaller ones (450W) in order to be able to better spread the light. Yes, you would have more wires, but the usage of electricity does not increase in accordance with the number of lights used – the “draw” only depends on the intensity. Two 450’s will not draw more power than one 900, for example. If you’re technically savvy, this is probably obvious. Being a non-techie, it seems noteworthy and I’m hoping it may help some others out there.

2. Old-fashioned wattage is NOT the same as L.E.D. wattage.

See someone complaining about the amount of light emitted/measured not adding up to the wattage as advertised?

Apparently, these customers don’t know what they’re talking about.

With led lights, there is a wattage and actual power draw, and those are two different things. You can find out the actual power draw by asking the seller or checking (or finding out from someone who has checked). Due to the many different types of light we have these days, wattage should not be used to compare true output across various types of lighting (such as HPS, LED, etc.). If you want to compare the given light, this should be measured in lumen.

The true wattage of the MARSHYDRO 300W LED grow light, for example, is approx. 140.
Beginners need to be aware that a led lamp is referred to as (for example) being 300 Watts, when that lamp consists of 5 Watt led’s and has 60 in total. However, that number (300 W) is not what the plants will receive and certainly not one-on-one comparable to an old-fashioned 300 W lamp. You need to use the wattage pulled from the socket in your calculations, and either add more units accordingly or use supplemental lighting to obtain the watts per square foot you need to keep your plants from stretching. In case of a 300 W led light, this would be approx. 140 W. One 300 W unit visually covers 9 SF set 4 feet above the tent floor, but the intensity of one unit is not adequate to raise healthy plants. You will need the 600 or buy 2 300s for a 9 SF area.

Speaking of “draw”, here’s another one:

Don’t be surprised if you measure the output of a 1200W full spectrum led grow light and only get a number as low as 525W. The 1200W means that the lamp is built up of 240 5W led lights, totaling 1200W mathematically. In the same way, a 300W light is labeled as such when it consists of for example 100 3W lights. These numbers do not refer to the actual intensity of the emitted light. For the 1200W for example, it is normal to measure a true light output of “only” 525W and that doesn’t mean the thing is broken. When comparing to HPS lights, these don’t match up to the same intensity, based on the name. The 300W Viparspectra, for example, would be used to replace an HPS light of approx. 125W.

3. Don’t expect to get the Hummer of L.E.D. grow lights, when you pay for a Nissan.

Quoting from a review: “There’s a reason that Black Dog and Spyder led’s cost as much as they do.”

MarsHydro is the brand this reviewer was talking about, although I imagine it can apply to all led grow lights reviews in the more basic and accessible price category. Overall, the led grow lights reviews for these different brands are similar, and at least three-quarter of all customers are very happy. It isn’t hard to understand that a led grow light costing three times as much will be of better quality, and why. When you’re simply not looking to spend such a high amount though, that knowledge is about as helpful as knowing that business class is so much roomier than a seat in economy class. As mentioned in the title, you can’t expect to pay for a “Nissan” grade L.E.D. grow light, and somehow expect to be delivered a Hummer or Ferrari class item. (No offense to Nissan. I just Googled cheap car brands, and Nissan was the first to come up.)

4. Colors vary, even among full-spectrum grow lights.

Even though two leading brands on the L.E.D. grow lights market (Viparspectra and MarsHydro) both make full-spectrum L.E.D. grow lights, there is some variation in color.

Since Viparspectra leans more towards the blue end of the spectrum, some like to combine these lights with Mars Hydro, another brand of full spectrum led grow lights which leans a bit more towards the red end of the spectrum. Enough red light is important during flowering, so you may want to take that into consideration and make a combined set-up with both brands, or supplement with some red when your plants are ready to move into the next stage.

5. How to gauge the right distance for hanging grow lights.

You may want to try hanging the light(s) a bit higher than what the manufacturer recommends because some users still report burns at the designated height. If you hang it higher and closely observe your plants, you’ll be able to tell from the stretch between the nodes or the space between the sucker leaves whether the lamp is too far away. Better to lower the height a bit, until you find the right distance for your plants than to have burn stains on those leaves sneak up on you.

6. Light penetration also differs from one brand to another.

When compared to the Gavita Pro 1000W with both being used in exactly the same circumstances (the same marijuana strain, nutrients, and other environmental parameters), the Viparspectra 1200W performed wonderfully in the vegetative phase and produced a dense flower at the top of each plant. The flowers under the canopy were loose and spindly, and clearly smaller. It seems the Viparspectra has a harder time penetrating to the lower layers of the plant than the Gavita Pro, which means it doesn’t work as good as a production flowering light.

7. How L.E.D. grow lights compare to fluorescent tube lights.

When you don’t know much about L.E.D. grow lights yet, or any other type of grow light for that matter, it can be helpful to learn something about not only L.E.D.’s, but also the others. At least I found this helpful for the sake of being able to gain an understanding of where different kinds of lighting stand in relation to each other. As far as L.E.D. lights and fluorescent lights go, three things stood out:

  • LED and fluorescent lights are the two best options on the market today.
  • Fluorescent lights can flicker, modern LED lights don’t have that issue.
  • The lifespan of LED is generally longer than that of fluorescent light.

LED grow lights reviews: Summary

Some of the points mentioned above are more than obvious to the experienced grower. As a beginner, it can be a little intimidating to figure out your first  L.E.D. grow lights purchase though! I knew so little, that I didn’t even know which questions to ask, let alone how to answer them. If you are starting to learn about the specs and workings of L.E.D. lights, hopefully my musings above are able to lend a hand in one way or another.