The perfect 100% coconut fiber based growing medium

See also: Coir Dust, a viable alternative to Peat Moss

The perfect 100% coconut fiber based growing medium. It can retain 8-9 times it's weight of water and has a high nutrient absorption capacity (CEC). It may be used alone or as a component of a soilless mix, mixed with perlite. It increases the porosity of soils and facilitates better root penetration. Clean coir has shown some anti-fungal properties, which is desirable when you try to root cuttings.

The cocofiber is mostly made of lignin (65-70%) and cellulose (20-30%) and peat moss has less lignin. High lignin content make cocofiber a highly suitable substrate to grow plants:

  • Lignin degrades very, very slowly in nature (how long does it take for piece of wood to rot in soil?)
  • Lignin is a very stable growth medium.
  • Lignin is a very inert material and any added soil additive and nutrients are fully available to the plants.
  • Near-neutral pH and negligible electrical conductivity promotes the development of favorable microorganisms in the root zone.
  • Lignin provides very good porosity for regular exchange of air.

These unique characteristics give GrowCoir a distinct advantage as a superior alternative growing medium over other types of substrates.

Property Growcoir Peat Moss (taken from different Internet sources) Water holding capacity (of dry weight) 8-9 times 8-12 times CEC (cation exchange capacity - refers to the ability of the medium to retain cations - Mg, K, Ca, etc. They are necessary for the plant). Potting media should have large CEC. Units of measure - meq/100g 60-130 80-140 pH - refers to the medium acidity. With time due to decomposing process pH drops. 5.4-6.8


Too acid for most plants. No microlife exists at such pH. Microorganisms break down fertilizers into "plant food". Peat-based mixes usually contains pH buffer.

Preparing soilles mix No mess. Just add water and it's ready. Have you tried to open peat moss bag in living room? Rewetting Easy. Hollow fibers absorbs water quickly. Well, you know how to make wet peat moss. It's hydrophobic and most commercial peat-based mixes contains wetting agent Decomposing time 4-5 years 2 years. When you repot old plant you can see it

Growcoir compressed briquette measures approximately 8"x4"x2.5".

To prepare mix:

Place a Growcoir brick in a large (3 gal or larger) container. Add 1.3 gal (5 liter) of water and leave to soak up expand for about 15 min. You can mix it manually to speed up expansion. You can dissolve appropriate amount of nutrients in water before pouring over brick. This will lock nutrients in your mix.

To make soilless potting mix add 30% of perlite and 20% of vermiculite. We used perlite and slow release Osmocote fertilizer

We got approximately 12 l (3.2 gal) of perfect mix.