Coconut Coir is the husk (mesocarp) of the coconut fruit that is processed and composted to produce a fine particle growing substrate. The husk contains 75% fibers and 25% pith on average and the fibers are separated from the pith to produce the final “coir pith” product. Advantages: Coir has good water holding capacity, a very high cation exchange capacity (CEC), and good rates of air filled porosity. The pH of coir will range from 4.5 to 6.5 depending on the area of coconut palm production and processing techniques. Disadvantages: Because coconut palms typically grown in close proximity to the ocean, levels of chloride and sodium can be higher than optimal so the coir must be properly leached and composted. Due to high levels of potassium naturally found in coir, the end product must be “charged” with calcium and nitrogen to balance the cation levels.