High Pressure Sodium (HPS) lamps are great for growing marijuana. Due to their red light spectrum and great light intensity per watt, they work well during the flowering phase.

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Lighting | Light cycle | Dark cycle | Light shortage | Light distribution | Light spectrum | Blue light | Red light | Nanometer | Light tight | Lumen | Lux | Reflecting light | Lamp height

HPI lights | LED lights | Compact fluorescent lights

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