As the by-product of coconut harvesting operations, coco coir is a renewable resource that has become a popular, effective grow medium. For the professional coconut industry, the husk of the nut has traditionally been a waste product. Coco coir is harvested year-round continuously. Environmental considerations notwithstanding, coco coir has many benefits for the grower—it retains water and is airy. Dating back to the early 1970s, innovative growers in the Netherlands repurposed coconut husks into coco coir. Today, one-third of professionally grown roses are grown in coco coir.
Consistency is one of the most important elements of a well-managed greenhouse as it pertains to producing positive economic returns. Coco coir reduces the occurrence of diseases, lowers maintenance requirements, increases water retention and oxygenates roots. It requires a new way of thinking about growing plants, but if used with forethought, coco coir can provide great benefits to your garden. For example, plant growth is optimized by coco coir holding onto nutrients and releasing them over a longer period of time—a 55 to 45 per cent fiber to pith ratio provides for better aeration and structure.
Since the actual coconut fiber doesn’t retain much water at all (three to five per cent), it does two things in the media: it creates aeration through the voids it leaves in the coir, and it also gives the media optimal structure to further prevent compaction, which is highly important to having a healthy root zone. The pith acts like micro sponges where the moisture is stored. The coco fiber and coco pith together make a great media with an excellent air to water ratio. Think of it this way: a car needs both fuel and air to run properly, much like plants need media and water.
If your car’s air filter (your media) is restricted or clogged, the car will not run properly since it is not getting the correct amount of air to mix with the fuel. Even though the car is still running, it is not running at optimal performance, just like plants won't grow properly due to an imbalance of air-to-water ratio in the root zone if the media is too saturated or compacted.
To get the best results from growing in coco coir, it’s important to source the material from a producer who manages the coco coir—both the fiber and pith—from its harvest to the finished, bagged product. When sourcing your coco coir, look for processors who triple-wash the fiber in a controlled indoor environment rather than processors who simply rely on the local weather patterns to clean the coco.
Ideally, the producer’s washing process should begin with the coco fiber going through a washing system that uses fresh, filtered spring water. A higher-quality coir product is then mixed with calcium carbonate to buffer the media and adjust PH, and subsequently sent through state-of-the-art automated processing equipment that measures its weight to be able to apply the correct amount of water, repeated three times, then sent to a press to leave 32 per cent moisture before aging.
With this triple-wash process, local processors can control the entire coir pith chain—from production location to the final user. This is what you want in your coco products. When the entire coir pith processing chain is handled by the same group, it improves the quality and success of the product.
Depending on where the coco is sourced, some types require little to no added materials such as perlite, hydroton or coco chips. North American-sourced coir—that which is made from coconuts grown in North America—contains all the fiber from the coconut so it has a fluffy, pillow-like structure that will never compact and will allow for great aeration using both the fiber and pith. Some manufacturers use just pith due to their primary export being the fiber, while other companies use all of the coconut husk to take advantage of its multiple functions.
For example, the fiber creates gaps (voids for plenty of airflow), and the pith are like micro sponges that hold moisture. For this reason, there is little to no need to aerate the combined fiber and pith medium, or mix it with perlite. Growers find that the airiness of the combination of fiber and pith is one of the main factors for a successful crop grown using in the substrate. Airiness of coir pith will be more or less based on coarseness and/or age of the material.
Further benefits of coir that is made using the entire husks include more retention of moisture that allows for the lignins to be present along with beneficial bacteria and fungi. Lignins are the magic component that encourages better microbes and healthier roots. Trichoderma is one bacterium that comes with select brands of coir.
They thrive among healthy roots and they kill detrimental fungi. In this situation, the coir is purposely not dried so that these beneficial bacteria remain just like they were when the coir was bagged at the plant. When using trichoderma-infused coco, there will be an increase in yields and overall health of your plants since the root zone is where all the action happens. This can greatly impact your final yields. In the end, better yields mean a more successful growing season.