what's the minimum light needed for vegging plants?

I'm planning on doing a 12 plant veg chamber and wanted to know if a 600 watt MH would be good for this. It would be in a 4'x4'x8' room and the plants would be in three rows of four.


I tried the search engine and if you've ever used it it's pretty hard to find exactly what you need, so sorry if this has been asked and answered.

you can do up to 24hrs if you'd like but at minimum no less than 16. Personally i do no less than 18hrs. Keep in mind the longer the light is on the more you have to worry about heat issues

I believe a 600 will work but for your size of space to grow I would
think a 1000watt would be the right choice.

Anyone else have a take on this?

Yeah, I know how long haha. I just wanted to make sure that they don't need more than that much light during the vegetative stage.

then i guess it depends how big you want them to get

Easy answer to this is as follows. For veg, MJ needs a minimum of 3,000 lumens per sq ft of canopy in the blue (6500k) colour spectrum for a min of 18 but preferrably 24 hours per day. Flowering, MJ needs a minimum of 5,000 lumens per sq ft of canopy in the red/orange(2500k) colour spectrum for 12 hours a day. A 600W MH light will emit around 60,000 lumens with a new bulb, more if the ballast has superlumens etc. You have 16 sq ft so you need a min of 48,000 lumens veg & 80,000 lumens flowering. A 600W HPS emits around 90,000 lumens. So, yes, the light will be sufficient for the space you have. 12 plants in a 4x4 space could leave them very tight however. When running a 4x4 space, vegging to 18" indica dominant plants, 9 will fit nicely in the space, remember, more plants does not mean more bud!!! Green mojo dude. W