Floodlight as Growlight ?

Have a 30W Led floodlight where the PIR section has failed but the Leds still work ok.

It gives out a good beam of light, but would it be any real use as a grow light in the greenhouse ?

 

Isn't it about wavelength or some such.

 

I doubt it will work.

Old fashioned grow lamps needed to use hundreds of watts because most of the light is unusable for photosynthesis.

Modern LED floodlights are efficient for us human sorts because they emit a very narrow band of light that we perceive as close to white, but there's not much red and blue in it which plants need.

Modern LED grow lights are also super efficient but not very nice for us human sorts because they only emit the red and blue bandwidths that plants need.

 

Sort of. But boffins use wavelength because colour is a subjective experience and can contain light of multiple wavelengths mixed together. Like when you mix paints of different colours.

Sometimes, just to confuse matters, you'll see the colour written as a temperature, but that's a tangent I'll try to avoid.

 

@ricky101 any light is better than no light.

This is from my personal experience not the interweb...

I started off with little incandescent bulbs like those in a parlour lamp and though they didn't help much, at least nothing died! Your LED is cheaper to run than those by far.

I moved on to shop lights - ballasts that hold fluorescent tubes and that was a little better.

Then I went "whole hog" and bought HPS - high pressure sodium which used gargantuan amounts of electricity and really heated up the area. And did a great job. But nasty expensive.

So I bought LED grow light strips off the internet and taped them to measuring sticks and then tied to hangers above the plants. This was to get what I could within my budget.

And now I use LED grow lights. They look like those shop lights but with strips of LED's where the fluorescent tubes/bulbs were. The LED strips did not get thrown out, they got shifted to the greenhouses, mostly just because they look pretty and are run off my solar powered battery array.

And if I run out of space, the excess goes under, you guessed it, regular lights.

LED's have proven to be by far the best. But, yes, any light (other than a black light) will help!

You can buy the LED grow light strips cheaply on the net.

 

Thanks Lori, we do have some small white leds strips and a proper led grow light but they are more suited to small areas, just thought this 30w floodlamp with is wide beam might work more to cover a 4 or 6ft bench.
As you say anything better than nothing.