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Mills Ultimate PK


£42.50 – £179.50


Mills Ultimate PK is a flower booster for use in the last two to four weeks of the plants life cycle. It has a ratio of 0-7-6, which Mills believe to be the most efficient blend after years of research. As with any other PK additive, the extra potassium and phosphorus are vital for developing heavy fruit in the final stages. The formula of Ultimate PK helps not only boost fruiting but stimulates a rise in flavours and aromas. The end result for the user is a heavier harvest with an overall better quality.

Ultimate PK is suitable for use with any feeding schedule, but of course works best with the Mills range. If you are using Mills C4, stop usin it before beginning with Ultimate PK (follow their schedule online for best results!). This is a clean additive and is perfect for use with any watering system, but as with any mineral feed, we’d recommend a clearing solution to prevent build up and clogging. Ultimate PK is also suitable for use with any substrate from soil and coco  to the hydroponic media like rockwool and clay pebbles.

Alternatives to Ultimate PK

At Straight Up Hydroponics, we have a range of potassium and phosphorus additives available in various forms! There are other PK brands, mono nutrients so you can make your own ratio and even powder form elements. You can see all of our nutrients on our website by clicking here.

Reg name - LPC Retail LTD
Company number - 10203576
Place of registration - Companies House, Cardiff
Business address - Unit B, Jarvis & Rowell estate, Burnham Road, Dartford, Kent, DA1 5BN

01322 273444