600W MH, switching to 600W HPS during flowering

Hey fellas, I have a question that pertains to lighting. I have a 600W MH bulb right now with 4 plants in 3 gallon pots. Also using organic soil and nutes. They're only about 8 inches tall presently and have been growing for about 3-4 weeks.

I read a post that said your light can dictate timeline or when to switch to flowering, in that if you have a weak light, spending extra time vegging is fruitless as a taller plant won't necessarily produce a higher yield as the light only travels a certain way down the plant (I hope I'm translating that correctly).

So I guess my question is how tall of a plant should I aim for with my lighting?

Thanks guys

Hey man, you gotta look at your plants and imagine them 2 or 3 times that size, you are correct in saying the light gets weaker the further it has to travel so a nice even canopy is desirable. I usually veg for 4-6 weeks depending how fast they have grown. Thats about the right time for the size tent i have. Peace

Depends on your grow space. I would let them veg a bit more. They are still young. You could flower them now, but 4 plants under a 600 hps? Unless it's a pure Sativa, you could veg to 20-24 inches! I wouldn't though. 12 inches minimum in my humble opinion. Which will be fast now. Or just wait for preflowers.

oh wait, how tall in the end? They stretch when you switch them. They can triple in size easily. Depends on the strain and your light. Just be careful with a Super Silver or anything like that. That shit will go through your ceiling! If you want them shorter, just top them. You can get 4 main colas if you do it right. I forget which node though, 5th i think? And if you don't, you will still get two main stems and some height control.