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Mills Ultimate PK – Phosphite Bloom Booster

Mills Ultimate PK – Phosphite Bloom Booster

Regular price £18.49 GBP
Regular price Sale price £18.49 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

A phosphite-based PK for a harder, heavier finish

Mills Ultimate PK is a phosphite-based bloom stimulator for the final stages of flowering. It works as a ripening hardener, driving up the production of essential oils as plants approach harvest to secure a fuller, more complete finish. The phosphite form is quickly available to the plant, making it well suited to the tight window in the last weeks before flush.

Key Benefits

  • Phosphite-based formula - a fast, readily available form of PK for late-flower uptake.
  • Increases yield - supports fuller, heavier flower development in the final weeks.
  • Enhances flavour and aroma - lifts essential oil production for a stronger finish.
  • Ripening hardener - firms and finishes flowers ahead of flush.
  • Improved plant quality - refines overall flower structure and character.

Flowers finishing soft or light?

Crops that stay soft or under-finished in the closing weeks usually need extra phosphite-based PK support rather than more base nutrient. Ultimate PK is timed for exactly that window, hardening and ripening flowers in the last stretch before flush.

How to Use

  • All media (late flower): 2ml per litre during the last 2-4 weeks of the flowering cycle, before flush.
  • Alongside base feed: add to your normal bloom nutrient solution.
  • Flush: discontinue and run plain water for the final days before harvest.
  • Tip: check EC after adding, as the higher rate raises solution strength.

Technical Specifications

  • Type: phosphite-based PK booster / ripening hardener
  • Dose: 2ml/L
  • Stage: last 2-4 weeks of flowering, before flush
  • NPK: 0-7-6 (as stated by Mills)
Feed Chart
Mills Ultimate PK · all media, late flowering
Stage Per 1 L Per 10 L
Last 2 to 4 weeks of flowering, before flush 2 ml 20 ml
Note — Add to your normal bloom nutrient solution, then stop and run plain water for the final days before harvest. Do not premix Mills concentrates — add to water only. Check pH and EC after mixing.

FREE Express Delivery on orders over £60. We aim to post same day on Express Delivery — order by 3pm Mon–Fri — and delivery takes 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.