I'm using the fox farm trio (big bloom, grow big, and tiger bloom). I did accidentally buy the hydroponic version instead of soil, the only difference is in the Grow big, where the N and P are halved relative to the soil and 50% more K than the soil. The younger one has been fed 25% of veg nutes, which is the 0.75 tsp per gallon of big bloom (0.01 -0.3 - 0.7[FONT=Trebuchet MS, Verdana, Arial, sans-serif]) and 0.5 tsp per gallon of grow big (3-2-6). I did also use the cal/mag nutes in both those feedings at 1tsp per gallon, so if the soil was burning them before it would have made worse. I just keep going back to the purple stems though as they are not a sign of burn, but they can be a sign of pheno...
I agree 100% about the cal/mag nute, I am staying away from it going forward in soil grows. The soil and dolomite lime should be enough for throughout the grow. I may transition to coco or hempy bucket at some point, so the buy was not useless i guess.
okay i think best solution is to flush next watering, to get any excess ferts out. This way if it is burn, it wont get worse. If symptoms continue then we can say it is a P def, and we can then feed with flowering nutes. But i think it would be risky to try to feed it and potentially make the problem way worse. I could do it the other way, but I think it would be more stressful on the plant. [/FONT]