Which LED light switches to use

My 600w LED lights have a switch for grow and a switch for bloom. Or I can turn on both grow & bloom and use them together. Is there ever a time that I would use both at the same time? If so, when and for how long? Or should I just use grow during the grow cycle and bloom during the bloom cycle?


I would consult my user manual…

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I have one of those lights as additional lighting. I have kept both switches on from day one. Will not hurt in flower or veg.


Thank you. I have 7 of them & I did not want to damage anything using them both ways.

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Glad to help. Good luck growing.

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Yea just keep them both turned out, it’s just a “full spectrum” light at that point. They utilize it all during the entire grow :slight_smile:


With both on it will boost your watts up anywhere from 80-120 watts

My light have the switch also you use the grow only for the veg and then when you turn them to 12/12 put both switches on and use both the grow and Bloom for the flower stage. And you will get a harvest similar to this or better


Awesome looking bud and thanks for the knowledge

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I use the veg switch for seedlings. I start at 24 inches and lower it about an inch a day to adjust the plants to the light intensity until I get it about 12 inches away. Then when it is strong in veg with a good root system I put the light back at 24 inches and flip on the bloom switch with veg still on so the plants can get full spectrum.

It’s the same effect as using a dimmer on those really nice full spectrum led lights like the HLG or the Mars Hydro ones.


A 2 cycle light has 2 switches, 1 for veg, you can run both at same time if running autoflowers, if running a photoperid you run the veg switch only then when u flip to flower you turn off veg switch and turn on bloom switch.

I have never encountered this problem or question so I’m glad I ran into this chat. #neveradumbquestion

You can run both together. It will not hurt the plants during veg. I have did it before, and still do, when using a light with both.

If you have a 2 cycle led light run your plant under blue light, 1rst switch on, if running photoperid plants run under full spec, both switches on, if flowering bloom, 1rst switch off 2nd switch on.

Hello there Doc, I’m using a new ViparSpectra LED. I believe the light has quite a lot of red and far red, my seedling is stretching and I have these 20 dollar cheap pick lights. Would a blue spectrum from these be beneficial and slow the stretch? Thank you as always mate!

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@Henry yeah some extra blue spectrum will help prevent more stretching. Lowering the light helps quite a bit too.

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Do you reckon these cheap lights will give off enough to make an impact?

Hey there Henry…I saw that you mentioned Viparspectra LED light…I’ve been running the Viparspectra 2500 since November 2020…I start all my seeds with the light…I also grow seed to harvest on many of the plants without any issues…Mind you, this is the first and only LED that I have used…
Happy growing

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Henry…I also use those cheap BLUE lights…25w from amazon
stretching…heat too high, light too strong (we start seeds at about 20% strength at about 12-16 inches and dome the seedlings (clear plastic cups work fine))
I add the blue lights and sometimes turn off the full spectrum for a portion of the day…so I get around 4-6 hrs of straight blue light. It really does wonders for the roots and helps keep the plants compact
Strain / genus…if you have Sativa heavy / dominant strains, they will be longer, lankier than indica…If stretching is an issue, try crumbling paper around the stem to support it…DO NOT BURY THEM…DO NOT WATER THE PAPER…just use it as a support. Make sure you have air movement / breeze to help the planst make STRONG STEMS

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It’s this one, it’s has a dimmer but is full spectrum with no switches, I’m now thinking it was a little hot in there for them about 28 degrees Celsius