I have 2 - 1500 watt LED red,blue,purple lights for my plants in a 4x4. They are in 10 gallon pots and stoped growing at around 9-12 inchs after 5 weeks. I recently got a COB white growlight and they have grown to almost 2 feet in a week. About 6-8 inch growth per plant since introducing 1 white light by replacing one of the red,blue,purple lights. Do I need this red,blue,purple lights? I was thinking of completly removing them and replacing them with another COB white light. Can I flower aswell with white? Or Will I need the red lights for flowering? The plants I have seperated in a seperate closet with the red,blue,purple lights have not grown at all or are VERY slow. So Im sure its a lighting issue now.
I love the COBs because they allow for different light levels in different places in the same tent, a necessity for those of us who grow multiple strains in the same large reservoir. The old blurple lights you used should've worked fine, and I wonder whether light was the issue. Of course white COBs are better, and if you can replace the blurple I'd do it. The 3500 K versions are said to be good from sprout to harvest. About 25 COB watts per sq ft works well.
the blurple may have been blue heavy and making shorter plants while the cob might be more red sided and induced some stretching. hard to say, are they any more dense of growth or?
I've recently tried 3 different lights, an ElectricSky, an HLG Rspec, and the COBs. They all work about as well as each other, but I prefer the COBs because of the ability to have different light levels in the same tent.