DIY Grow Lights

Hello there,

I took a look at this and was about to order the parts for my office plants, but then i realized - the LED's required for this project were not described, and are not in the parts inventory - can you post a suggested LED as standard LED's are likely not the best for plants!

Peter

I had the same question, as we use LED's every day. Look at the spec sheet on the Mouser site and you'll see these are very "cool" at 5,750K. Would like to see a spectral plot, and could do that by digging deeper into the manufacturers part number's spec sheet.

Would this also work to replace a light box for people for Seasonal Affective Disorder?

It looks all right until someone finds a way to use it to grow drugs.

You could add a red LED to warm things up a bit.

If you click on the first part listed and then click the picture, download the PDF and it will show the LED's are there.

Could be used to grow pot plants.I am sure though they have their own growing lights already.

No offense but the schematic for the photocell/intensity adjustor is awful. It should, in theory, be a simple loop but I can't figure out what this "gnd" is, what connects to L and 1 on the pot... I don't really know how to read schematics so I aked an electrical engineer I know who told me the schematic isn't very good. Does anyone have a better schematic, or even better, can you give a step by step instruction on how to solder this up?

Looks to me like the photocell is inline with the positive lead, which then feeds to the positive post for the light tubes. Then the negative feed passed thru the 10K ohm resistor, to the pot, thich then feeds to the neg lead on the lights. I can't figure out what the "L" and the "1" are got on the pot diagram, or if they're anything. If you can help: didyounowrong@gmail.com

You can go to http://www.optekinc.com/viewparts.aspx?categoryID=73 to learn more about the Optek designer light kit.

Has anyone actually built this kit yet? What would be a good book to use as a reference for people that are not familiar with building electronic devices?

I'm not sure LEDs are bright enough for plants. I have 28 or so plants in my room, and they don't even seem happy with the light from CFL lights. The ones that I can't fit right in my south window sill get all yellow and lose leaves before spring when I put them outside. And, as for the temperature thing, LEDs are low-temp; that's why they're so efficient.

Article makes no sense. How are you gonna have hot lights that can sit right in the pot?

Great project idea.
Why incomplete information?
s/Stanhbaker

Duh! $35.00 for the kit.
Go buy a string of bright white LED Christmas lights for $5.00 at WalMart or Home Depot. Create a loop of chicken wire around your plant and hang the lights to it. Now you have 25 to 50 LED's and a total cost under $10.00!

Fifteen LED's for $35.00 in a kit! Come on guys, this is the best you can do for us? LAME

Someone said they hoped it couldn't be used to grow "drugs". I agree! But if it could be used to grow Marijuana (certainly not a drug, no overdose, no addiction) that would be great.

Please let us know if it works for growing marijuana and grow some more!

Uhm, these leds don't produce ANYTHING for a plant to sustain itself on. There is more to light. really popsci? Like, really?

Uhm, these leds don't produce ANYTHING for a plant to sustain itself on. There is more to light. really popsci? Like, really?

Uhm, these leds don't produce ANYTHING for a plant to sustain itself on. There is more to light. really popsci? Like, really?

Uhm, these leds don't produce ANYTHING for a plant to sustain itself on. There is more to light. really popsci? Like, really?

LOL. I think whoever wrote this article is 'on drugs'.

Check this out for some real low wattage high lumen lamps ...

www dot littlegreenhouse dot com/accessory/lights.shtml

have a look at the datasheet for the LED kit at the optek website.

www.optekinc.com/datasheets/OVPL5W3K.pdf

data sheet has retina damage warning, so i assume the leds put out some amount of UV.

Do not waste your time on this idea. Also, do not believe everything you read. Do research! I did out of necessity - I'm a chef so growing my own vegetables and herbs greatly appealed to me.

Here's what you need to know:

LED lighting is VERY inferior to Fluorescent and (HID) Hi-Intensity Discharge. You will not get the results you are looking for with LED growlights and furthermore your apartment or home will look like a 1970's disco with all the red and blue going on. This will also mask the plants natural beauty.

People assume LED lights will work well because they can visibly see red or blue as opposed to Fluro and HID's obvious white light. In reality, you don't have to visibly see red and blue for the benefits - white light can harness the entire spectrum of visible light so seeing colors doesn't matter. LED's just use a colored film over the light to visibly show the red or blue. They are very weak when compared to the aforementioned lights.

Whatever the case, red and blue are the only colors that will yield you great results with plants. Don't waste your time on orange, yellow, green, etc. Trust me on this. There is a range for optimal growth and only red and blue fall in that range.

You have two choices that will yield the best results that are not extraordinarily expensive:

1) CFL Fluorescent
2) Metal Halide (HID)

Look to this website for further details - http://www.littlegreenhouse.com/guide3.shtml

Pay attention to the amount of watts you require, the amount of lumens reflected, and the distance the light must be from the plants. Buying some reflective paper to bounce the light back up into the plant is a good idea too. All of these materials can be found on that website.

@chefrob

First, that is not how an LED works. They do not simply use colored film to mask the other light, rather they emit a different wavelength of light and operate on different voltages for different colors.

Second, do not tell people, "There is a range for optimal growth and only red and blue fall in that range." Surely you have graduated from high school and therefore must know that in fact red and blue light are on the opposite ends of the visible spectrum. That means that any visible light is "in the range" simply because all visible light falls between red and blue on the spectrum. Take a rainbow for example, the light bends through a prism of water separating the different colors and red and blue are on opposite sides. In fact violet is actually outside of the range of red-blue on the spectrum but violet is almost the same spectrum as blue.

I am not trying to be rude I just wish to help you and others realize your mistake.

This seems to be a dangerous device and presumably you do not seriously grow houseplants or you would see this.

This scheme presents an electrical hazard in which both plants and humans could get quiet a shock if not electocuted. Unless one is growing most cactae---it is impossible to keep water, mosture away from these lights---if the scheme works.

Suggest you go back to the drawing board, grow orchids and other houseplants that you have to water daily or at least once a week and see if you get a shocked in the process of watering with accidental spills.

Several sources say red and blue LEDs are best (mostly red, maybe one quarter blue) because chlorophyll absorbs most strongly in red and blue. LEDs produce light in a rather narrow spectrum, so you can convert your electricity into the kind of light the plants accept. White light is a waste of energy unless you want to see their natural coloration with your eyeball.

And I'd also prefer a design which keeps the light away from water; I didn't look at the schematic but hope it's a low voltage current-limited design with stray voltage cutouts.

@philsbored

When I wrote my initial reply to this article, I was hoping to offer my advice (in laymen's terms) to novice growers in order to save them time, money, and frustration. Nevertheless, there are always people who think they know what they're talking about and want to get technical like you do.

I understand that (all) LEDs do not used a colored coating, but due to the cost-efficient manufacturing of phosphor based LEDs with distinct color layers, that is exactly what most consumers who purchase these lights “cheaply” from places like Walmart are getting.

LEDs are more suitable for NASA spaceships than for plant growth. Reason being, they use less energy, have a longer lifetime, smaller in size, and have faster switching capability - all features attractive to conserving electricity in space. Hi-Pressure Sodium and Metal Halide lighting more closely mimics natural sunlight and is therefore more beneficial for plants. A simple $300 HPS or MH setup would be a better option in almost every way (relevant to optimal plant growth) and much less expensive than a quality LED setup which can run up to the thousands. Hi-Intensity Fluorescents are even a better option, in my opinion, than LEDs. They utilize warm and cool “white light” which, when used in conjunction with each other, can harness the entire visible spectrum. However, the misinformed, like yourself, seem to believe that white light is a waste. New technology for LEDs also utilizes white light but at a higher wattage and with slightly more lumens.

What you obviously didn’t understand from “the range for optimal growth statement” was that I was breaking it down in laymen’s terms. I would never presume that someone would be so incoherent as to interpret that the way you did. Of course I know that red and blue are at opposite ends. But if you want to get technical, the optimal growth parameters are between 400-520 nm on the blue band and 610-720 nm on the red band. It is within this range that peak blue-vegetative growth and/or red-flowering budding occurs.

Yes, ultra-violet is close to the visible blue band, but it is in no way the same spectrum as it can be harmful to plants since it contains UVB & UVC rays occurring within 200-315 nm. Hopefully you are informed enough to know that you shouldn’t use ultra-violet lighting for your plants.

I am not trying to be rude, I just wish to help you realize that most of your advice is incorrect and the true parts of your argument are not warranted in this situation.

Optek LED design kit (Mouser #828-OVPL5W3K; $35) listed in the parts list actually prices at $76.53. The other stuff is pretty much correct. Although for those prices I might as well just leave all the lights in my house on all the time to feed the plants.

Chefrob, I don't understand what you're saying. First you say that white light is a waste, then you say that it is not. Why mimic natural sunlight when you can do better with just the narrow red and blue bands?

And I'm not trying to be rude but nobody mentioned ultraviolet.

JRS ONE,

I never said that white light was a waste - I said that most people think that you either need a red spectrum or blue spectrum bulb - which is wrong. If you actually read about this or learned by experience, you would know that harnessing full spectrum white light is the best for vegetative growth. Blue spectrum bulbs are used in conjuction with natural sunlight in greenhouses around the world. It is used as a supplement, not as a primary growth unit. Therefore, if you plan to grow indoors, an equal amount of cool white and warm white high output fluorescents will do a better job than your single blue spectrum bulb at 6500k with no accompanying sunlight.

However, for flowering stages, one HPS unit will yield the best results. White light isn't as necessary as the vegetative stage here, but a small range of blue light is beneficial. Too much red spectrum light pulls the chlorophyll from the leaves turning them gray. (THIS DOES NOT MEAN WHITE LIGHT IS A WASTE)

To reply to your ultraviolet statement - again, if you read the posts you would understand that philsbored was making a clear distinction between light that falls in the visible spectrum and beyond. With what is outside the range, and what is inside. I was clarifying that light which falls outside of the visible range (AKA ULTRAVIOLET) can be toxic to plants. Please read fully before you plan on discrediting someone's advice.

Ladies and Gentlemen, as an old electronics technician, I mean old in the tube and resister era trained by the U.S. Navy, I believe after reading the comments on the light spikes, that some have lost themselves in the strict letter of the article, not seeing the spirit of the editor. I believe that a lot of the "experiments", as printed in the articles, can be in a range from novice to expert and are meant to stimulate the mind and not really intended as the optimal solution to a problem.

I often shudder at some of the projects, as far as safety for the untrained experimenter and compliment the editors in their warnings often given to that end. If you are going to try a project, make sure you are prepared for the extreme end of the spectrum, especially with electricity. I can tell you that familiarity breeds complacence, I can tell you this from experience as I have taken thousands of volts in shocks by just not paying attention, the key here is that experience kept the end result at a minimum, usually numbness and tingling.

As for the light spikes, they are inherently dangerous, any time you stick an electrical apparatus into a wet environment you risk shock. Please don't do it unless you KNOW what you are doing. As for the comments on the technical and non-technical aspects, get real friends, it is a fun project if you are prepared to do it and want to learn. Again, electricity + moisture + inexperience = death, bottom line! If you really want a good grow light, go out and buy one with a good warranty and reputation. In the long run it will be cheaper and safer. If you want to have fun experimenting, GET PREPARED and prepare for the extra expense. If you think you can build a radio for $4.99, start making them or just go buy one made in china.

I believe the spirit conveyed by PopSci is in expanding your imagination. YOU REALLY CAN'T COMPETE WITH THE FAR EAST FOR COST, but you can learn a new hobby and have fun.

It looks all right until someone finds a way to use it to grow drugs.
http://www.hedefnakliyat.com

I am new to this. How can I get rid of that stupid GMC ad and read the parts list, every time I close it it comes straight back?

I used to deal with a grwo light manufacturer and you really do need to check the lumens carefully especially the lights that are manufactured in china. www.selfbuildconservatoriesuk.co.uk

We don't sell LED grow lights at www.dreamconservatoriesonline.co.uk but we have come across a lot of people who are really keen gardeners and they use all kinds of lighting techniques to get the most out of their plants all year around. Naturally having a green house or out house of some sort really helps but if you don't have that then the next best thing is a DIY greenhouse hydroponic system with the ultimate ratio of red+blue light. You can get them almost everywhere nowadays.

Great article, I am certainly going to build one for my aquaponics experiments this winter. Skimming the comments, there are lots of mentions/concerns about LED's and if they are adequate - certainly your standard LED's are not, but the 1W, 2W type LED's ARE. Keep in mind the idea here is to provide additional light during the winter season, not to compete with HID or HPS or even CFL lights. The nice thing about these is they LOOK decent. They look almost decorative. I do not think I would want a big honkin HID light hanging in my living room, or even an ugly CFL lamp for that matter. Maybe these will be the trick to get my aquaponics project an edge.

Some days I feel just like this article…doing whatever I can to get the job done.

http://www.towinbet.com/