DP's DP (Dutch passions Durban Poison)

Switched over to flowering strenght nutes this week. Started showing the first few pistils here and there. Still just defol and training. the training has helped to keep the ladies quite short for a sativa dominant plant. waiting to see if they will stretch more or this is it. Think I may have been a bit late with the nutrient change as the one plant that was doing extremely well before seems to be slower now, and some of the tips are showing sign of burn. Also, this plant shows some serious purple on the stem and shoots. I dont think its a cal-mag deficiency but have no idea what else it could be besides genetics.