I'm not really sure
@Lucky Luke . This is what I was reading
For ultra dense bush in my science in cannabis I have found the following gives the best grow results using LED's. and high PAR capable nutrients like our Nukeheads flower power package.
(24 hour on lighting)
250 PAR - Seedlings
450 PAR - teens up until around 9 inches of height (they should be ultra dense and bushy)
500 PAR - Switch to 12/12 lighting
750 PAR - Mid bloom
850 PAR - mid-late bloom
400 PAR - Last three weeks ( shade them in simulation )
This seems to work great and the shading at end harvest time ensure the plants very low photo-response and activity is not over-burden causing light burn do to she's so pregnant she cannot keep up .. so letting her rest those last three weeks causes a phenominal girth
and trich output !