Mycelium WorksCultivation tools & knowledge
StageInoculationColonizationFruitingHarvestingProcessing
Substrate & Preparation

Coco Coir

Shredded coconut husk pith with excellent water-holding structure.

Illustration of a coco coir
Typical specifications
FormCompressed brick or loose
Brick yield650 g brick to 8 – 9 L water
Moisture target70 – 75%
NutritionVery low
pH5.5 – 6.8
TreatmentPasteurise or sterilise
Substrate & PreparationSmall to large batches

Overview

Coco coir is the fibrous pith of coconut husk, sold compressed into bricks. It holds water well, resists compaction, and has very low nutrition, which makes it forgiving for growers who want a contamination-resistant bulk substrate. It is the standard base for beginner-friendly fruiting substrates.

Primary stage: Colonization

Where it fits in the grow

Hydrated, drained and mixed with vermiculite before spawning.

Safety & handling

Compressed coir bricks are not sterile and can arrive with mould spores. Always pasteurise or sterilise, even when using a low-nutrition recipe.

Practical advice

Buy horticultural coir rather than the coco coir sold for reptile bedding — the latter is often washed with salt water and can carry a high sodium load.

Educational only. Mycelium Works does not sell this or any other product, and we receive no payment for listing it. Specifications vary by manufacturer — always follow the maker’s instructions and local regulations.
Related

Tools that pair with this

Gypsum

Calcium sulphate amendment that loosens structure and buffers pH.

Colonization Guide →