In this series of posts, we are going to introduce you to a perspective world of coir substrates 🥥
Coconut substrate has gained its popularity for hydroponic and soilless growing thanks to its unique properties and sustainable nature. It’s a perfect choice for many crops and an asset for many growers all around the world.
Coconut is familiar for many households but its use goes far beyond culinary uses. Cosmetic, fuel, construction, medical, and agricultural industries regularly use this wonderful natural product so no wonder the coconut tree is often referred to as a “tree of life” 🌴.
Agricultural use of coconut mainly implies the use of coir, a thick fibrous layer surrounding the hard, internal shell, and the outer coat of the coconut. Only mature coconuts are used for substrate production as their coir turns brown and fibers become stronger. Coir has high lignin content, which allows it to last long, hold more water, and not shrinking after drying.
To produce the substrate, coir has to first be separated from the coconut. Husks are soaked in water, which softens and swells them, and makes them easier to remove. After being separated from the endosperm, the coir is dried and then washed and crushed into finer components:
Coir fiber makes up 30% of the husk and is extremely durable, strong, and elastic. It is one of the hardest and strongest natural fibers thanks to its high lignin content. You can often see coconut fiber in the floor mats and doormats, mattresses, and brushes. In agriculture, you could see it in weed control mats, which let water and nutrients get to your plants while keeping the weed out. Coir fiber is naturally resistant to moisture damage, rotting, and molds. It is added to coconut substrate to create air pockets and provide oxygen to the roots.
Coir pith makes up 50-70% of the husk and looks very similar to the peat moss. It is a non-fibrous, spongy, lightweight, and fluffy material that binds the coir fiber in the husk. Its properties can vary depending on the ripeness of the coconut, but the one used in the agro-industry is mostly brown and comes from mature coco. Similar to coir fiber, it is resistant to moisture, bacteria, and fungus.
Coir chips are essentially coconut husks that are chipped into small parts. They are added to the substrate to improve aeration and air to moisture ratio inside the medium, which promotes the growth of plant roots. It is often used as bedding and litter for reptiles, rabbits, spiders, and other pets.
Coir fiber, pith, and chips are mixed in different proportions to make a perfect substrate with properties tailored to specific plant’s needs 🌱!