Should You Make Your Own LED Grow Light? DIY Instructions

Due to the high price of LED lighting, I get asked all the time about whether making a homemade light is worth it. The answer really depends on what you are trying to grow, your mechanical skill level, and the amount of free time you have available. Below you’ll find a general discussion on what you should consider before building your own light. At the end of the article I provide resources for those of you who are determined to make your own light.

What Plants are You Growing?

The first thing you need to consider is what are you trying to grow? I’ve read three or four do-it-yourself LED grows and they are exciting, informative, and they bring out the do-it-yourself spirit in all of us. However, one thing that they all have in common is that they are growing very, very small plants (cilantro, sprouts, etc.). I’m talking like three to four inches here. I have yet to run into a homemade LED grow light that has grown a plant over a foot tall.

If you are simply looking to start a plant out or if you are looking for a supplemental light, then a DIY LED grow light might not be a bad option. If you are looking to grow a three foot tall plant from start to finish without the use of any other light (including the sun) then you are going to need a heavy duty grow light like the ones you can buy here.

Here’s a picture of the plant grown by one of the most popular DIY grow lights out there:

It’s cool and I give the guy props for creating the light, but I like my plants bigger than that.

Do You Save Money with a Homemade Light?

Many people want to try their hand at making their own LED light so they can save money. Trying to save money by being resourceful isn’t a bad idea, but you should take a look at some of the prices of the individual components of a light.

Components of a bare-boned LED grow light:  (We’ll be shopping at Radio Shack which I realize isn’t the cheapest place. Still, it will give you an idea of what we are dealing with).

Total Price for a light that will grow you a 3 inch plant = $251.90! And this doesn’t even include your time.

The truth is you can find the LEDs in bulk much cheaper somewhere else (not at Radio Shack). For example you can buy a kit with 256 5mm LEDs for around $40. If you were really resourceful and found great deals then you could probably make your own homemade LED grow light for around $50 (not including your time).

This still doesn’t make sense because you can buy better LED grow lights on Amazon for less money.

Here’s one that costs $50 and it will probably work better than anything you can make at home. It also comes with a hanging kit.

There are some other really cheap LED grow lights on Amazon that are probably better than anything you could make yourself (though I hate to say that). Take a look around. Keep in mind that most of the cheap lights you will find on Amazon are only useful in three circumstances: supplemental lighting, the vegetation stage, and growing very small plants from start to finish.

Don’t Forget the Heatsink

If you do decide to make your own grow light, don’t forget the heatsink. If you have read my series about how LED lights work, then you’ll know that they operate very differently from other types of lighting. The difference in the way these lights produce light leads to less heat diffused, but that doesn’t mean that the actual diodes where the electrons are being jumbled around won’t heat up. If these diodes get too hot, then they break. If you don’t have a heatsink on your homemade light, then don’t expect it to last very long.

All the LED grow lights being manufactured, even the cheap UFOs, have heatsinks installed. When these lights were first designed, they were introduced to the market without heatsinks. People became very frustrated when their 50,000 hour lights ended up only lasting 5,000 hours.

Heatsinks are usually made of aluminum and/or copper. They aren’t expensive to build, but it does take time to learn. You can go here to read more about the importance of heatsinks in grow lights.

One more item you might want to throw on your homemade LED grow light is a fan. The fan is used to bring cool air into the casing and blow off some of the heat on the heatsink. Isn’t it funny how the price of do-it-yourself projects always pile up like this?

My Opinion

If you really like building things like this, then I recommend you give it a shot. I honestly believe that 99 out of a 100 people won’t be able to build anything comparable to what is being sold. Most people simply lack the necessary equipment, experience, and skills. If you want to build one of these because you want the experience, then please do so (and I’ll provide some resources below). If you want to build one to save money, then good luck to you, but I’d recommend against it.

Resources

I’ve read through five or six do-it-yourself LED grow light projects. Here are some of the resources I found most helpful. Hopefully these will help those of you who are determined to build your own light.

http://www.dabblings.net/subpage2.html – This guy has made two different lights. The site has some great pictures about how to wire the diodes on. It also has a great list of parts that you’ll need. He made his light for about $40. He doesn’t ever mention heatsinks which makes me a bit worried.

http://www.homegrownlights.com/index.html– This site has kits with everything you need to build an LED grow light. You simply have to assemble them (the cheapest version is $45). Note that I’ve never bought a kit from this place so I can’t attest to the quality of the kits. If nothing else, you can hop on over to the site to get a feel for what you need to build your light.

http://www.bcb.uwc.ac.za/ecotree/photosynthesis/spectrum.htm – A good site for understanding the wave-lengths you’ll need for you light.

http://www.instructables.com/id/Growing-Plants-With-LED-Lights/ – A guy from England provides detailed instructions on how he made an LED grow light.

http://www.instructables.com/id/high-power-LED-grow-lights-M.k2/ – Same guy from England provides instructions on a higher-powered light.

http://www.cheapvegetablegardener.com/2009/01/cheap-led-light-and-grow-box.html – A guy uses Christmas LEDs to make a small grow box. This is by far the cheapest setup I’ve seen!

Below is a YouTube video with a good look at what your homemade light might look like. The video might give you some ideas for your own project.