How It Works — Prepare Your Raw Coco Coir Brick

Use a clean bucket, trug, or mixing tub with a minimum capacity of 75L — the brick expands significantly and needs room. A standard 70–100L garden trug or large mixing vessel is ideal. For hydroponic drain-to-waste setups, a 50–60L mixing bucket works well. Make sure the container is free from residues of previous media or chemicals.

Add 20 litres of clean water to the container before placing the brick. Warm water speeds up expansion — cold tap water works too but takes longer. For best results, use reverse osmosis (RO) water or pH-neutral tap water. Avoid hard water with very high calcium if you are running a precise nutrient programme, as it may affect your EC baseline.

Place the brick into the water and allow it to hydrate fully. Do not rush this step. Full expansion takes 20–30 minutes. Occasional stirring or gently turning the brick helps ensure even water distribution throughout. A properly hydrated brick produces a consistent, lightweight medium with no dry pockets — critical for uniform root zones across your grow.

Once fully expanded, break apart the softened coir using gloved hands or a garden fork. Work through the medium thoroughly until you achieve a light, even consistency with no large clumps or compacted zones. Well-fluffed coir retains the air channels that give roots the oxygen they need. This step directly affects aeration, drainage, and ultimately your yields.

Coco coir can be used as a standalone substrate or blended for specific growing goals. Use 100% coco for hydroponic drain-to-waste systems, seed germination, and propagation trays. For container and raised-bed growing, blend with compost and perlite to suit your crop. We recommend starting with our 50:30:20 general mix (coco:compost:perlite). See our Mix Ratios page for crop-specific recipes including tomatoes, strawberries, leafy greens, and hydroponics.