MILLS ULTIMATE PK 200 LTR

Phosphite-Based Late-Bloom PK Finishing Supplement, 200L

The final two to four weeks of bloom call for a different kind of phosphorus and potassium support than earlier in flowering, one that reaches the plant quickly rather than waiting on slower mineral salts to break down. Mills Ultimate PK is a phosphite-based bloom supplement, using a highly bioavailable form of phosphate to support ripening, fruit set, cell structure, and flavor and aroma development in that late window.

This 200L size of Ultimate PK is sized for large-scale commercial production.

Key Features & Benefits

• Phosphite-Based Formula — a highly bioavailable form of phosphate for fast uptake late in bloom.
• Late-Bloom Timing — designed for the last two to four weeks of the bloom stage.
• Supports Root Systems — formulated to promote vigorous root systems and nutrient uptake.
• Supports Oil & Terpene Production — formulated to support essential oil and terpene development.

Who Should Use Mills Ultimate PK

Growers finishing the bloom stage who want a fast-uptake phosphite supplement to support ripening and flavor development in the final weeks before harvest.

About Mills Ultimate PK

Mills Nutrients formulates its five-part program — Basis A and B, Start-R, C4, Ultimate PK, and Vitalize — at the company's research and production facility in the Netherlands, tailoring each product to a specific stage of the growth cycle. Ultimate PK is the system's late-bloom finishing supplement, timed for the final weeks before harvest rather than the full flowering stage.

Frequently Asked Questions

When should I use Ultimate PK?

Use it during the last two to four weeks of the bloom stage, once flowering is well underway. It's a finishing supplement, not something to start at the beginning of bloom.

What is Ultimate PK made from?

It's a phosphite-based supplement, a highly bioavailable form of phosphate that plants take up faster than some mineral-salt alternatives. That speed matters in a finishing window that only lasts a few weeks.

What does Ultimate PK support?

It's formulated to support ripening, root systems, nutrient uptake, and essential oil and terpene production. Those are the areas most active in the final stretch before harvest.

How do I apply Ultimate PK?

Add it to the reservoir at the label rate once you're in the final two-to-four-week finishing window, layering it onto whatever base and bloom feed is already running. Because that window is short, most growers mark a calendar date rather than relying on visual cues to decide when to start.

Which size should I choose?

Smaller gardens do well with the 1L or 5L container, mid-size grows use the 10L or 20L size, and commercial finishing rooms typically order the 60L or 200L size. Because Ultimate PK only runs for two to four weeks per cycle, a smaller size often lasts longer than it first appears.