Need help understanding COBS

Hi so i need help understanding lights a little. Now when i read about 3500k vs 5000k LED lights i understand that this is a different intensity in the colour of the light, but what i do no understand is how do i know what is best for my plants needs? What intensity should i choose and why

welcome aboard and great question!

all cobs start off as sharp mono-chromatic (450-460 nm) blue light emitted by the array of diodes, which is converted to a wider band of red light (500-700 nm) by the yellow/orange silicone layer on top. how much of the blue light is converted to red light is up to you. you can pick a COB with a thin phosphor layer like a 5000K-6500K, which will give you a lot of "lumens" bur not necessarily what your plants want. you can go for a very heavy phosphor layer like a 2200K-2700K which will convert a lot of the light to redder light which "loses lumens" but provides the stroong light plants like in flowering

short answer: flowering plants like 2200K-4000K. vegging plants like 3000K-5000K. if you need an "all-in-one" light that can do both its really hard to go wrong with 3000K-4000K.

Hope that helps!

The best way I can describe the Kelvin(K) scale in lighting is like a blacksmith heating iron in a fire. As the temperature(K) of the metal increased, the color our eye sees changes from straw to red to blue/white. Say 2K is red and just like the iron in the fire, as the temp(K) goes up the light from the iron gets bluer.
So what does that mean for growing? From what I have read about this subject it seems that during vegetative growth, the plant responds best with a spectrum that is more blue shaded. When flowering the plant wants a more red shaded spectrum. I have found that 4K Vero's produce much better veg growth compared to the 3K version but the results are flipped when flowering. I suspect that a bigger split may enhance that difference. 3500K is a good 1-light choice that will give really good results-can it be improved? Sure, just cost more money for parts...