Adding lights in flowering

I’m growing under four 600-watt HPS lights. The plants have outgrown the lights. I’ve added another tray and have hung a 1,000-watt Sunmaster Warm Deluxe MH.
I’m three weeks into flowering. My friend told me that if I add the additional 1,000-watt light at this stage in growth, it would have a negative effect rather than a positive one. Is this true?


No, it isn’t true. If the plants have outgrown the space and the garden is being spread out, the plants will use the extra light. More light will fuel photosynthesis and result in additional flower growth.

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