There are a lot of things to consider when you are building your own LED grow light. One of the lynch pens of the whole process is the LED grow light itself. If you choose a low quality light your grow light will only produce at the best mediocre results. This cheap type of setup can be seen all over the internet, and is a huge reason that LED lights get such a bad name when it comes to growing plants.These high priced cheap lights produce plants that look sickly and for the most part are only good at getting your seedling to grow just a little bit. If you choose to build your own grow light, just know the old adage you get what you pay for. Don’t expect miracles out of a bundle of blue and red Christmas lights, these lights work just don’t expect them to grow a forest. So now that you know not to get the really cheap stuff I bet your wondering ok genius which ones do I pick? We will be going over this in a second but first let’s look at some common questions.
What colors should I use for my grow light? – Believe it or not most people when building a light think that they need either a green or white light. This is well for the most part wrong as green light is not easily absorbed by plants as they reflect most of the light because of their green chlorophyll, and the white light does not contain enough amounts of correct colors on the color spectrum to grow plants effectively. So which colors should I use? In short you would be best going with blue and red. There is a lot of talk going on about whether or not other parts of the color spectrum should be added but, there are a lot of successful lights that only use blue and red , the reason that this is true is because this is where most of the uptake for photosynthesis happens in plants. Most of the peaks on graphs show uptake being in the blue and red areas. If you however feel the need to add more than just blue and red there is some evidence that supplanting with a small amount of green light can help
Now that you know which colors to choose you need to know how many of each to get and what each one of those colors does.
If you are trying to grow only non flowering plants, herbs, or some vegetables or are trying to use the LED growing light as a plant starter or for vegetative growth then you only really need to use blue LEDs in the 450 nm – 470 nm range. Blue LEDs will give your plants strong roots and stalks as well as strong leaf structures, there are some theories about them also fighting off certain diseases but I can’t find any real proof.
If you are trying to grow huge fruits/flowers and put out a lot of them, then you will want to go with all or mostly all red LEDs in the 630 nm – 660 nm range. The red spectrum tells the plant that it is time to flower and get ready for the winter so start sending out as much seed bearing items usually in the form of flowers or fruits as possible.
What if I want to have a plant light that does both? Ok so you want the best of both worlds, who doesn’t right? If you want to make sure that you are giving your plant the right amount of each light then you will want to be in the 6:1 – 9:1 ratio of red to blue lights. For example of you have 45 red 1mm LEDs then you would want to have 5 blue 1mm LEDs to equal out the ratio. This type of setup is called a dual band setup. What this means is that you will have only two color bands in the grow light. This type of setup is going to be your most common one that you will see on the market.
So do I need a Tri-band, quad-band or any other type of multiple band type of LED grow light? In my opinion it’s like getting a car with power windows over a car with manual roll up windows, yeah its nice and yeah it might make it easier on you but you don’t really need them to drive down the road. Yeah it’s cool to have all the extra spectrum color variations in there with your basic red and blue setup and yeah it might help you out a little but it’s not at all necessary to have them. If it were the case that you absolutely needed to have more than two spectrums then all of the major LED grow light producers would not be selling only dual band grow lights as their top sellers and only sellers. So take that into consideration when buying a grow light from the producer and ask yourself if the “power windows” are really worth all that extra money.
Now let’s talk a little bit about wattage. There is a lot of talk around about which is the best wattage option 1w LED, 3 w LED or the 5 w LED. And the survey says- the 1 watt LED is the best, why you say? Because when you increase the wattage on individual LEDs they drop in Lumen output. This is the short and dry answer there is a whole lot more to it than that but as far as you need to know the 1 watt LED will do what you need it to as far as growing your plants are concerned.
What about the size of my LED? As you may know there are a lot of different sizes of LEDs on the market today. Most range in size from 3mm to 10mm, so which one is better, like most of our human instincts the adage more is better is often applied but it’s actually big things come in small packages that rings true here. I personally use 3mm as they provide better intensity than larger mm LEDs.
Picking out the viewing angle of your LEDs, once again there is a lot of controversy over which viewing angle to pick and if viewing angle matters. In my opinion it does matter to some degree, but if you stay in the middle of the road such as a 65 degree area will do you just fine, you can go with wide angle 120 or acute angle 8-30 degree LEDs if you choose but just remember that for the most part only about 15-20% of your light is going to get past the plants canopy, and the more you spread out your light the weaker it is going to be. But going to too acute is going to cost you a lot more in terms of LED per area of light covered.