Metal Halide lights are used during the vegetative growth stage of cannabis plants that are grown for medical marijuana. Metal halide lights produce the blue light spectrum marijuana plants need to grow big and strong.
I personally use 250w Hortilux Blue and 400w Hortilux Blue halide lights in my grow room. I use the 250w halide for clones that have just rooted, then when the plant is 10 inches tall I use 400w Blue Halide to grow my mother plants.
250w Metal Halide Lights to Grow Cannabis
Using the best metal halide light for growing marijuana will make the largest difference in the size of your bud harvest. You can see in my photos and videos how well these Blue Metal halide lights actually work. I only recommend the stuff I use in my grow house!
400w Metal Halide Lights for Mother Plants
I have found that growing marijuana mother plants using a 400w Hortilux Blue metal Halide Light works much better than the 1000w I used in the past, which created too much heat for the plants to grow healthy. I run my vegetative grow room metal halide lights 24 hours a day. They will last approx 1 year before you need to replace the bulb.
These are the exact same 400w Metal Halide Lights I use in all of my grow rooms!