The box that my hps bulb came in says: Plantmax hps lamps are PERFECT for all purpose growth as well as fruiting and flowering. So with this being said, my question is why cant i use this bulb for all stages of growth?
Hi Don, You sure can use that light for all stages, including veg. However HPS is pretty expensive to run, when you can get away with CFL, T5s, or other types of veg lights for that portion of the operation. The more red spectrum range (think of the Fall sun) that the HPS just happens to fall under helps kick off chemical reactions in the plants to flower, above and beyond just the shorter 12/12 photo period. The more blue end of the spectrum (early Summer skys!) helps kick off a chemical reaction in the plant that helps them grow better above and beyond the long photoperiod. So vegging with an HPS may not be as efficient (the expense to operate compared to the growth) than with other types of lights, but it may very well be used. Hope this helps. Cheers, Past