Recently, there has been a lot of interest in PK boosters and supplements. These are available at various concentrations, the amount that should be applied can vary, and the ratio of potassium (K measured in K2O) to phosphorus (P measured in P2O5) can also vary. All this variation means that growers may be confused about what they’re actually applying. To create a little more clarity, we have summarised everything that growers need to know.
CANNA products for the flowering phase contain plenty of potassium and phosphorus. However, there may also be periods during the growing phase when the plant needs more P and K. Simply increasing the dosage, but using the same formulation that was applied during the previous weeks, is not possible because that formulation also contains other elements such as nitrogen, magnesium, iron and other trace elements, which are already at their maximum levels. So the only other option is to add more P and K.
In PK 13/14 there is 130g of phosphorus (P2O5) and 140g of potassium (K2O) per litre of nutrient formulation when dissolved in water. When we use this formulation, we apply almost as much extra phosphorous as potassium, in addition to what is contained in the Flores flowering formulation. But it is important to remember that Flores already contains a certain amount of P and K.
Therefore, if we apply 1.5 ml PK 13/14 in addition to CANNA Flores in the 3rd generative phase, we are providing:
|130 gr: 1000ml||130mg/ml x 1.5ml||195mg of P2O2 (phosphorus) on top of the Flores formulation|
|140 gr||140mg/ml x 1.5ml||210mg of K2O (potassium) on top of the Flores formulation|
These additional amounts end up in the substrate, gradually changing the ratio present in the substrate, which still contains largely Flores, and producing the desired effect on the plant.
This is exactly why CANNA recommends PK 13/14 as an additive. You should only use it if the plants have already developed enough flowers or fruits to need additional phosphor and potassium. And if that is the case, apply the supplement according to the supplier's guidelines. In the end, the combination of a nutrient formula for the flowering phase and a PK supplement will result in the right ratio for the plant at that stage in its life cycle.