Yes, I always do for the last week or so. Your flowers look nice and ready to me, so I would stop feeding and go to plain water until harvest. At this stage, leaving your plants much longer will lead to increased THC breakdown into CBD and CBN, producing a more heavy and drowsy stone, which may be your preference, however if you prefer a more clear and up stone, harvest should have occurred when all but the very last pistils were brown and the last 5% or so of the pistils were still white.,
as this gives a true indication of plant maturity, rather than relying solely on trichome colour. I have grown plants with 50% honey coloured trichomes already, in only their third week of flowering! And yes, it was a Sativa, for all those playing along at home! Once all the pistils have completely browned, the plant is well and truly passed her reproductive peak, approaching death and with an almost stopped metabolism, and this is what causes the THC to breakdown into CBD and CBN, the slowed metabolism. Fresh THC can therefore not be replenished faster than it is breaking down, causing a plant with diminished psychoactive ability, but with enhanced therapeutic value, as indicated by the rising levels of CBD and CBN. So while late harvested cannabis may relax you more and make you lethargic (couchlocked), it doesn't actually get you as "high" as flowers harvested while at the peak of health, which will give you a more mind expanding experience. This is my personal preference, I want to get high, not fall asleep and unable to move! Hope this helps,.... Organoman.