PK 13-14

Hesi PK 13-14 is a phosphorus and potassium bloom booster specifically formulated for hydroponic and coco coir cultivation. The 13-14 values refer to the phosphorus (P2O5) and potassium (K2O) concentration, delivered in a highly concentrated form to meet the elevated P and K demand cannabis plants have during the bulk of their flowering phase.

Unlike the base nutrients, PK 13-14 has no nitrogen — it's a pure PK supplement that layers on top of your existing nutrient program without altering nitrogen balance. Use it progressively through the later stages of flowering: Hesi recommends starting at 2.5 ml per 10 litres in week 4, ramping up through weeks 5-7, with a flush in week 8. This progressive dosing mirrors the plant's increasing PK demand as buds develop and density builds.

Compatible with coco and hydroponic systems (Hesi's soil line has a separate phosphorus-plus product for soil PK boosting). Works in both recirculating and drain-to-waste setups. PK 13-14 is the classic Dutch bloom booster formula — the same composition as many competing bloom stimulators — delivered in Hesi's concentrated form.