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Mills C4

Mills C4


Mills C4 is an advanced bloom stimulator additive designed for fruiting or flowering plants. It encourages:

  • Quicker and more abundant fruit
  • Promotion of plant growth and vitality
  • Increased oil and sugar production
  • Development of denser, harder, and heavier fruit and flowers
Mills C4


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Mills C4 - 1L:
Mills C4 - 5L:

Mills C4

Mills C4 is a powerful flowering fertiliser, comprising a unique combination of micro- and macronutrients, carbohydrates, trace minerals, and bio-stimulants. C4 ensures that you achieve high-yield harvests and improves the quality of your fruit. Thanks to the fertiliser's strong biostimulants, plants produce huge amounts of sugars and essential oils. C4 accelerates your plants' growth, stimulates flowering and enhances the taste of your fruits. Mills C4 is suitable for all growing mediums including hydroponics, run-to-waste hydroponic systems, and organic soil;


  • This Mills fertiliser accelerates the development of your plants;
  • The fertiliser promotes denser, heavier and tastier yields;
  • Supports increased production of essential oils;
  • C4 breaks down deteriorated and dead root matter;
  • The formula transfers beneficial nutrients and carbohydrates to your plants' flowers;
  • Improves your plants' immune system.

The Science of Mills C4

Mills produced the fertiliser to efficiently and quickly activate flowers' growth. The formula establishes dense fruit sets in the beginning and middle stages of blooming. In turn, you'll enjoy massive produce with increased levels of essential oils.

The fertilizer comprises high amounts of potassium and phosphorus, which are responsible for the production and ripening of flower heads. Also, C4 delivers the required micro and macronutrients, trace minerals and carbohydrates to developing flowers. This way, C4 optimizes your plants' sugars and oil production.

C4 organically dissolves dead root matter and turns it into carbohydrates, using a blend of humic or fulvic acid, L-amino acids, and cold-pressed seaweed, ensuring accelerated growth.

How to Use Mills C4

Growers use C4 starting with the 3rd week of the blooming phase. Use 0.5 ml/L during week 3. Use 1 ml/L during week 4, 1.5 ml/L during week 5, and 1 ml/L during week 6.

When used with Mills Basis A&B, Mills C4 alters the NPK to have higher phosphorus and potassium levels to help initiate the growth of fruits and flowers. C4 is predominately organic and has zero biological activity, allowing it to work in conjunction with beneficial biologics to feed tender flower sites and maintain the overall health of the plant.

Best Practices

Mills C4 is an easy-to-use one-part nutrient, designed for the blooming phase. Mix the nutrients into your water reservoir and mix thoroughly.

If you're growing in clay pebble, rockwool, coco or any other hydroponic system, make sure that you maintain a pH level between 5.6 and 6.2. Because the pH level rises naturally, keep it at the lower end of the scale when you mix the nutrients into your water tank.

If you're growing in organic soil, you shouldn't regulate the pH level. In case you want to adjust it, keep the pH between 6 and 7. Because it will rise naturally over time, keep it towards the lower end of the scale.

Store the formula in a dark, secured, and cool area. Also, keep it away from very high or very low temperatures. Ensure that you keep the fertilizer away from children.


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