100W LED height

Had no problems keeping a 100w at any distance close as you want before it gets warm, I mean these are plants afterall they grow under a infinitely brighter light in nature and it’s hot too under the sun so you shouldn’t have problems with a cool led

Beat way to know is to take a look at the manufacturer website to know the distance recommended for that specific lamp. Not every 100w led lamp have the same light efficiency, light repetition or light spectrum so there are many answers to your question.

There are light meters available for download to your phone.. I found mine actually fairly accurate and helpful. Some LED makers are really vague about instructions. And your gonna really up the light intensity for Flower Soo see where your light is actually at.. my sweet spot is 28-32" on my Aglex and then 22-24" on my Vivosun.. Another led I had, had a sweet spot of 18".. Sorry to much information but you get the idea :).

Most LED grow light companies recommend keeping them 45-60 cm away while they are in veg. then once they are in flower 30-45 cm.

Even if I touch the surface of the LED, it's not that warm. It should be ok.

Hey friend, Personally with LEDs i think around 24-30 inches is where i try to stay with these young sensitive plants. So anything above about 60 cm but keep an eye out for stretching. I also would say that all leds are different....whether they have built in fans or not. So be wary of how hot your model is, because the plants may be able to handle the light intensity but not the heat, and vice versa, some models can be closer. So try putting your hand over the plants to see if you feel a lot of heat on your hand in 15 seconds and that can give you an idea of the right distance too. Happy growing. ✌️

I just thought that because it's a low wattage led i should put it closer

With it being such a low wattage you don’t have much to worry about. If your leaves start curling up that tells you it’s to close.

Yep.

@Quackerjack So atleast 45cm with this 100w led?

Veg should can be from 18-24 inches. Flower can be 12-18 inches.