OK people have flowering lights, why is that? do you not want normal photosynthesis during flowering? The more sciency the answer the more ill like it Cool!
i use HPS when flowering and MH for veg the MH light has more blue where the HPS has more yellow and orange
Check this link out http://forum.grasscity.com/absolute-beginners/529078-how-light-works-tackling-question.html
Metal Halide/daylight cool white bulbs are used for the vegetative state High Pressure Sodium/soft white, warm white bulbs are used for flowering. the bluer light used for veg is used to mimic the days in summer or spring when the days are long and has more of the cooler light spectrum as to the more orange/yellow lights are used for flowering to mimic the shortening days in fall where the light spectrum has more of the warmer spectrum(usually gettin close to harvest time) and make the plant think the season is starting to come to an end so basically the plant thinks time is counting down so it starts to reproduce and finish before the end of the season. thats what i have always gotten out of it.. i havent really studied the shit out of that area of growing but enough to understand it like that. someone correct me if im wrong
exactly what the person above me said. that and hps is high intensity discharge, so it creates fuller, thicker, and heavier buds, which is why sooo many people use them over cfl's for flowering.
so you mean that flowering doesnt just depend on light ratio ie/ 12/12 but also depends on the colour spectrum weird.
Plants will flower under blue light, but they prefer a warmer color. The closer you get to what the plant would in nature, the better your yield.
FYI, you can get a MH bulb that has the yellow/orange spectrum in it. Thats' what I used on the last grow I just harvested. I think it came out swell.
i just dont understand the physics By cutting off blue light you just stop your carotenoids from being excited which absorb light energy for use in photosynthesis, and protect chlorophyll from photodamage. Niether of which should have an effect in an indoor grow, mid summer it makes sense to help the plant avoid photo damage from intense summer sun, but you never have the 10, 000 lumens/ft^2 that the summer sun makes. Just doesnt make sense when they break down they release carbon but then why bother ever having blue light :S?
First off, a 400 watt HPS bulb gives off 55,000 lumens. 10k per square foot is easily attainable, and is the recommended value. As for why even having blue light, you don't need it. You could use a HPS throughout the whole grow. It just vegs faster under a MH light.
Again, you're simulating what happens in nature. When the daylight hours are reduced and the color of the light changes, plants go into survival mode. Make flowers, make seeds, and eventually die.