really?? ive always gone in to every grow starting with 18 hours of light ..from a seedling.
am i wrong by doing this? i use a MH to start and then go into my HPS for flowering
I would say this is not needed. If you dont pay for the electricity, have plenty of room and heat is not an issue, then it might be an option I suppose.... I have fantastic success with keeping the seeds dark until they sprout to about an inch (still with their pre-leaves semi closed), this takes a couple of days. Then a day or so natural light then at the 1" stage I introduce them to my fluorescents for a couple of weeks or so for the vegging and then move them to my HPS for the rest of the vegging and for the remainder of the flowering.
I always do a 24hr veg and 12hr flower : why? you may ask.... Because Im not paying the electric costs.
and I reason that a longer day of light is better than a shorter day of light and since plants dont sleep why not??? Also I reason that the massive change from having 24hrs then just 12hrs of light 'sends' the plants into flowering with a real punch. relative to the 18/12hr used by some. Although this is IMHO and have never done the 18/12hr thing so cannot compare.
never used Metal Halides (many do) so cannot talk about them. I would however say its best to keep any project as simple as, so I choose to use just one type of HID, 600W HPS' (less to think about)
peace