Mills C4
Updated 18 Oct 2026
Mills C4 is a liquid bloom stimulator that encourages early flower sets and assists carbohydrate delivery and the production of essential oils. It is a concentrated mix of sugars, vitamins, amino acids and humic acids. NPK 0.7-3-3.
Usage & Instructions
Start from week 2 of flowering at 0.5 ml per litre and increase to 1.5 ml per litre later in bloom. Follow the Mills Regular growth chart.
Product Specifications
Description
Mills C4 is an advanced bloom stimulator for the flowering phase. Its complex mix of sugars, vitamins, amino acids and humic acids supports early flower sets, carbohydrate delivery and the production of complex essential oils. Highly concentrated. Part of the Mills Regular (Red Line) programme.
Available variants
Nutrients Regular
All products in the Nutrients Regular range.
Mills Basis A
Mills Basis A is part A of the two-part Mills Basis A & B mineral base nutrient. Used together in equal amounts, A and B supply all macro- and micronutrients in balanced proportions for both the vegetative and flowering phases. NPK 3-0-1.
Mills Basis B
Mills Basis B is part B of the two-part Mills Basis A & B mineral base nutrient. Used together in equal amounts, A and B supply all macro- and micronutrients in balanced proportions for both the vegetative and flowering phases. NPK 0-4-3.
Mills Start-R
Mills Start-R is an organic-mineral root stimulator for seedlings, vegetative plants and early bloom. It promotes a healthy root system, reduces transplant shock and combines organic and mineral components in one bottle. NPK 5-0-0.5.
Mills Ultimate PK booster
Push your plants to the limit. Give your plants the extra horsepower they need at the end of their flowering cycle with Mills Ultimate PK.
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Mills Cocopeat is a pH-neutral coco substrate of coco fibres and coco gravel with a light consistency that balances moisture and aeration, encouraging strong and extensive root systems. Supplied in 50 L bags.
Mills Light Mix
Mills Light Mix is a peat-based growing mix with sphagnum and perlite for commercial applications, moderately pre-fertilised with NPK 14-16-18 fertiliser. It uses carefully selected and filtered mosses and has an EC of 1.2-1.4.
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