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Hesi

Hesi PK 13/14 Flowering Booster

Hesi PK 13/14 Flowering Booster

Regular price £6.99 GBP
Regular price Sale price £6.99 GBP
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Order by 3pm Mon–Fri — we aim to post same day · FREE Express Delivery over £60 · 1–2 working days · Free Wembley pickup

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Description

The standard bulking PK, in Hesi's formulation

Hesi PK 13/14 is a phosphorus and potassium booster for the bulking weeks of flower. PK 13/14 is an industry-standard ratio, and the differences between brands come down to purity and how well the solution holds together in a reservoir.

Key Benefits

  • The standard bulking ratio - widely understood and easy to slot into any schedule
  • Clean in solution - holds in a reservoir without dropping out
  • Straight PK - no passengers you may already be feeding
  • Any base feed - mineral or organic
  • Pairs with Hesi Boost - minerals and metabolism from two different products

Flowers that stop gaining in the last few weeks

Demand for phosphorus and potassium climbs sharply in the second half of flower, well past what a base feed carries. The plant plateaus, and the gap between a good yield and an average one is decided right there. Timing matters as much as dose - too late and there is nothing left to build with.

How to Use

  • Weeks 4 to 6 of flower: 1 to 1.5 ml per litre at every watering
  • Do not stack: if you are already running another PK, use one or the other
  • Taper: stop about a week before harvest and flush
  • EC: reduce the base feed as the PK goes up so total EC holds
  • Watch for: clawed, dark leaf tips mean too much

Technical Specifications

  • Role: Bulking PK booster
  • Ratio: 13/14 phosphorus to potassium
  • Typical dose: 1 to 1.5 ml per litre
  • Window: Weeks 4 to 6 of flower
  • Use with: Hesi Boost
  • Media: Soil, coco, hydroponics
Feed Chart
Hesi PK 13/14 · soil, coco and hydroponics
Week Per 1 L Per 10 L
Flower weeks 4 to 6 — at every watering 1–1.5 ml 10–15 ml
Note — Do not stack PKs — if you are already running another, use one or the other. Reduce the base feed as the PK goes up so total EC holds, and stop about a week before harvest to flush. Clawed, dark leaf tips mean too much. Check pH and EC after mixing.

FREE Express Delivery on orders over £60. We aim to post same day for next-working-day arrival — order by 3pm Mon–Fri. Delivery is 1–2 working days. A few harder-to-stock or large, bulky items can take a little longer — we'll tell you if that applies to your order. Heavy-item surcharges are always shown at checkout before you pay — we only ever charge what delivery costs us. Prefer to collect? Free pickup at our Wembley store.