Discover
If you want to provide your plants with the best possible foundation, Mills Substrates Regular are the perfect choice. Our world-class substrates were designed with demanding growers in mind, tailor-made to complement your unique grow style perfectly. They combine ease-of-use with superlative quality, ensuring your plants have what they need to flourish.
This line covers five options, from clean coco based mixes to fully loaded peat blends. If you want a neutral coco base that you can steer with your feed, there is Mills Cocopeat. If you want more air in the root zone without turning the pot into dust, Mills Coco and Cork adds fine cork for extra aeration and root development, using 75% RHP certified coco peat (RHP is a quality certification used in horticulture substrates) and 25% fine cork. Cork is the signature ingredient here. It holds water like a sponge while keeping air in the root zone, and it stays springy over time, so you get long-lasting air pockets instead of a mix that compacts.
If you prefer soil-style growing but still want that extra oxygen around the roots, Mills Soil and Cork blends peat, coco chips, and fine cork, plus enough nutrients to cover the first 4 to 6 weeks of growth. For bigger rooms and faster workflows, Mills also offers two peat-based commercial-friendly mixes. Mills Light Mix is peat-based with added sphagnum and perlite, pre-fertilised with NPK 14 16 18 (nitrogen, phosphorus, potassium). Mills Top Mix is a blend of black and white peat with perlite and Mills fertiliser, with NPK 14 16 18 and added calcium nitrate.
Cocopeat is pH neutral with a strong balance of moisture and aeration
Coco and Cork increases aeration using 75% RHP certified coco peat and 25% fine cork pre-fertilised with NPK 14 16 18 and calcium nitrate.
Soil and Cork includes nutrients for the first 4 to 6 weeks of growth. It has slow-release fertilisation that feeds gradually over an extended period.
Light Mix is peat-based with sphagnum and perlite, pre-fertilised with NPK 14 16 18 and built for commercial applications
Top Mix uses black and white peat plus perlite, with NPK 14 16 18 and added calcium nitrate
Discover
Mills Cocopeat suits growers who want a clean start and full control. Because it is pH neutral and designed to balance moisture with aeration, it works well for frequent feeding and more control. If you run coco nutrients, automated irrigation, or a regular hand feed routine, this is the straightforward choice.
Mills Coco and Cork is for growers who want the same coco base but a lighter, airier root zone. Cork increases aeration, which helps roots develop faster and reduces the risk of waterlogging when you are pushing bigger pots or higher frequency watering.
Cork is also a smart choice from a sustainability perspective. It’s harvested from cork oak bark that regrows every 9–12 years, is biodegradable, and offers an organic alternative to inorganic aeration additives like perlite. Cork production is low-energy, and cork oak trees absorb large amounts of CO₂.
Mills Soil and Cork fits growers who like a soil style pace but still want extra oxygen in the medium. This is the one for growers who want a simpler run. It suits beginners who aren’t measuring pH or EC (electrical conductivity, the strength of your nutrient mix), and it works well for outdoor and guerrilla grows where you can’t mix feed every watering. The slow release fertilisation feeds gradually over time, which means less frequent feeding and less nutrient washout.
Mills Light Mix is built for commercial applications, and it reads like it. Peat-based, sphagnum and perlite included, pre-fertilised with NPK 14 16 18. It is a solid option when you need consistency across many plants, and you want a medium that behaves predictably with a standard feeding schedule.
Mills Top Mix is the heavier, more loaded option. The black and white peat blend and perlite give structure, and the mix includes NPK 14 16 18 plus calcium nitrate. This is the one growers reach for when they want a richer starting point and a medium that carries early growth with less intervention.
