Canna PK13-14 is supposed to be used in conjunction with your regular bloom fert (it's a bloom additive not a bloom fert). I think it's just P and K and your plants need more than just macros but it depends on what you're using for soil. I've used promix which is great, peat based soiless so no nutes in it, you have better control of feeding ratios but since it has no nutes your feed has to be balanced or else it might get some micro deficiencies, I still love it over any other top soil. Root growth is great with the promix cause it's so light. Top soil might have enough micros in it already. But the dilution ratio's they give on the bottle is for use along side your regular bloom fert.