This may sound silly, but i was looking at the Nitrogen on PFerts and it says it contains Urea and Potassium Nitrate. What is Urea and if it's potassium nitrate, is there still a need to dose potassium?
Synthetic urea is created from ammonia and co2. When nitrogen is mixed with urea it becomes water soluble. Urea is found in most plant and lawn fertilizers. Potassium nitrate is the source of mineral nitrogen and the urea is what lets the plants absorb it. Potassium (K) is a different element altogether.