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HEAVY HARVEST PK PRO is highly concentrated, meaning that only a small amount is needed, making it outstanding value for money!

PK PRO is a superior blend of phosphorus, potassium and poly-electrolytes that will give your plants all the added nutrients they require to achieve more abundant fruit set and hard cell structure. PK PRO has been established through research and repeated side-by-side field testing against leading pk boosters. The addition of Poly-electrolytes improve the transportation of phosphorus and potassium within the plant maximising their effectiveness.

PK PRO has been formulated to be used from the moment flowers begin to form right through to the flushing process. The dosage steadily increases along with the plants need for phosphorus and potassium. Steadily increasing the dosage not only provides the plants with the optimum amount of nutrients but also signals the plant to flower harder.

Benefits of PK PRO:
  • Increases the size of fruits and flowers
  • Strengthens cell formation in flowers
  • Improves water and nutrient transportation
  • Increases plant rigidity
  • Reduces the amount of base nutrients required.
Directions of use:
  • Use from week 3 of the Flowering phase until the flushing process
  • Shake bottle well
  • Week 3 mix into nutrient solution at the rate of 0.5ml per 1 litre (1:2000)
  • Week 4 mix into nutrient solution at the rate of 0.8ml per 1 litre (1:1250)
  • Week 5 onwards mix into nutrient solution at the rate of 1ml per 1 litre (1:1000)
  • Once all additives have been added use the base nutrient to reach the desired EC value
  • Once all nutrients have been added to the nutrient solution adjust the pH to between 5.5 and 6.5
  • Do not prepare the solution for more than 7 days ahead
  • Do not use in combination with products containing hydrogen peroxide (H202).
For best results use alongside the rest of the HEAVY HARVEST additive system.