Which one to use: PK 13/14 or Shogun Warrior PK 9/18?

Article Summary:
Which PK booster should you use and why.

What is a PK Booster made of?

• The P in PK is phosphorous (P₂0₂)
• The K in PK is potassium (k₂0)
• The numbers (PK 9/18) refer to the % of phosphorous and potassium in the PK booster.
• PK 9/18 means there is a 9% phosphorus, the rest is water and other elements used in the production of the booster.
• Similarly, PK 13/14 is 13% phosphorous and 14% potassium with the rest being water.
• PK 9/18 is a plant specific formulation whereas PK 13/14 is monopotassium phosphate which is a fertiliser used in mainstream horticulture for a wide range of plants.

Why we need a PK Booster in the flowering stage

• Additional potassium is required to encourage the plant to flower and increase yield.
• A PK booster is designed to encourage the production of larger flower sets (bigger buds) rather than leaf production.
• Because potassium competes with calcium and magnesium for uptake, we want less of this in the vegetative stage when the plant requires more calcium and magnesium for cell production and chlorophyll production  (5)

What is the best ratio of PK? Is it PK Warrior 9/18 or PK 13/14

• For specific (flowering) crops, PK 9/18 is the optimum ratio of potassium to phosphorous (5)
• For general purpose crops, PK/13/14 is ideal as it covers a lot of requirements and hence it is used in general agriculture.
• PK Warrior 9/18 is highly concentrated with a usage rate of 0.5ml/L making PK warrior 9/18 the cost effective choice.

• Studies (5) have shown that the optimum concentration of nutrient of the best inflorescence yield (buds and flowers) is: (N) Nitrogen 184 mg/L, (P) Phosphorous 59mg/L, and (K) Potassium 175-340 mg/L

• The optimum PK booster ratio for specific varieties is PK Warrior 9/18
• Additional potassium (K) is essential for increased yields & flowers
• PK Warrior 9/18 is 3 x concentrateed as PK 13/14 giving you much more for your money
• Too much phosphorous (P) as found in PK 13/14 will damage the microbial life in the rootzone which will inhibit growth

• Use from day 21 of 12/12 photoperiod
• Use at 0.5ml/L
• For 1 week only you can give an additional boost at the rate of 1ml/L
• Continue using PK Warrior 9/18 until the final week where we recommend using Shogun Dragon Force (only) for last minute yield improvement and to drive oil & terpene production

1. Cockson, P., Schroeder-Moreno, M., Veazie, P., Barajas, G., Logan, D., Davis, M. and Whipker, B.E., 2020. Impact of phosphorus on c_nnabis sativa reproduction, cannabinoids, and terpenes. Applied Sciences, 10(21), p.7875.
2. Westmoreland FM and Bugbee B, (2022) Sustainable Cann_bis Nutrition: Elevated root-zone phosphorus significantly increases leachate P and does not improve yield or quality. Front. Plant Sci. 13:1015652.doi: 10.3389/fpls.2022.1015652

1. "Roles of Arbuscular Mycorrhizas in Plant Phosphorus Nutrition: Interactions between Pathways of Phosphorus Uptake in Arbuscular Mycorrhizal Roots Have Important Implications for Understanding and Manipulating Plant Phosphorus Acquisition" by Sally E. Smith, Iver Jakobsen, Mette Grønlund, and F. Andrew Smith, published in Plant Physiology in 2011.

1. Saloner A, Sacks MM and Bernstein N (2019) Response of Medical Cann_bis  (Cann_bis sativa L.) Genotypes to K Supply Under Long Photoperiod. Front. Plant Sci. 10:1369. doi: 10.3389/fpls.2019.01369

1. Bevan L, Jones M and Zheng Y, (2021) Optimisation of Nitrogen,Phosphorus, and Potassium for Soilless Production of Cann_bis sativa in the Flowering Stage Using Response Surface Analysis. Front. Plant Sci. 12:764103. doi: 10.3389/fpls.2021.764103