How much do large plants drink?

Say I have large enough plants to do 100 gallon smart pots justice. How much are these going to consume a day? I really have no experience with gigantic plants. Was pondering planting some seeds now. Get a solid 3 months veg in under MH. Thoughts? 2 months veg good enough if put out at an appropriate time when they won't start to flower? I know what my girls drink inside in coco, but honestly it's not going to compare vs the full sun. I also veg under T5's for my coco so again apples to oranges.

I can only grow 6 plants so I'm going to make the most of them. Also trying to decide on genetics still, although I have some things that are promising. NLxTexada Timewarp, Skunk x TW, Heribei (Herijuana cross acclimatized to dutch climates which is good for me at the 49th), Herijuana (also suited to this climate but an IBL and not as vigorous as I'd like) and quite a few over at RCMC I'm considering. BC Coastal Haze, Skunk x GG#3 and Bluebonic x GG#3. Also GG#3.

PS: Gonna put out plants @ around 4 or 5 ft tall.

i water my 100's with mini sprinklers....i would leave them on for a hour like once every 3 days...
but other factors will make them dry out faster or slower...sun,wind,heat and plant size...
i veg for like 2 months before putting them out...but i would do around 3 under t5...

also enjoy the sun!!!!!

What mini sprinkler did you use?

i started with this kit...and got some extra parts...
soil and shit gets stuck in the spinning sprinkler heads and they stop spinning...
this year im planning on using 2-4 gph drippers..
also i should of said my soil mix is really light and fluffy, it almost imposable to over water...

http://www.dripirrigation.com/drip_irrigation_categories/174

I would second the drip irrigation instead. Much easier to control and not overwater. KISS.

How many drippers do you plan on using per plant? In the 100's specifically.

one 4 gph on the 100's smaller plants will get 2 gph drippers ..is the plan...i might add more if i need to...
my soil is heavy in coco and wicks well...so idk....

I'm open to hearing what your mix is as well. I have quite a bit of coco to mix in. I estimate I'm going to need 3 yards total. I have about a yard of good coco to use. Figure I will use it in lieu of peat.

Good to know, gives me a rough idea on the expected water use. I have some water concerns (less than a lot of people). But I wanna keep them perfectly hydrated. If you're short on water sometimes you can't. Sounds like I should be fine though without having to haul in water from elsewhere.

the 100's got something like
2 1.5 cf bags FFOF
2 2 cf bags happy frog
.5 4cf bag of perlite
2 2cf bag black gold coco
1 25 lbs nature's source worm castings
6 cups dolomite lime
few cups rainbow mix...