Optimum NPK Ratios for Hydroponic Cannabis Nutrients:

Life StageNPK
Vegetative/GrowHighMedium to HighHigh
Flowering/BloomLowHighHigh

N-P-K stands for Nitrogen-Phosphorus-Potassium, which are the three most important plant nutrients. These are what the 3 numbers listed on the front of all nutrient bottles stand for (Potassium is represented by “K” because chemists use the symbol K in the periodic table for potassium).