Anyone who has ever cared for plants has probably purchased commercial potting soil at some point in their lives – but did you know that almost all commercial potting soils are made from peat – a non-renewable resource which exists in very limited quantities on our planet, and has be harvested from peat bogs which are thousands of years old? When I first heard about this I had no idea! Most peat comes from wetlands and swamp forests where it forms naturally from decomposing material and helps regulate carbon as well as support wildlife. To put this into perspective, a loss of just 5% of the carbon stored in Britain’s peatlands would equate to the UK’s total annual green house gas emissions (according to the International Union for Conservation of Nature). Given the importance of peat to our eco system, it hardly seems wise for us to continue to remove it just so that we can grow houseplants. Because of the ecological issues with using peat in soil, some growers like Costa Farms are searching for more sustainable alternatives for use in plant soil. On a recent trip to Costa’s Miami farm, we were introduced to one such substance called coconut coir. Coconut coir is attractive because it’s a byproduct of the coconut industry that is not eaten or used as fuel, and on top of that, it actually promotes plant health. Read on to find out more about this eco-friendly growing medium and flip through our pics of coir being processed.
So what exactly is coconut coir? If you’ve ever handled a husked coconut (they’re typically brown and have a hard shell), you’ve touched the tough coir fibers that surround it. As you might imagine, coir cannot be eaten, so for many years it was simply regarded as a waste material. Today, coir fibers are used to make ropes, doormats and packing materials, but it’s also a surprisingly good medium for growing plants. According to Costa, coconut coir has an outstanding water-holding capacity (it can absorb 8 times its own weight in water) and the fibers act like mini-sponges, retaining water for long periods of time while releasing nutrients in ideal increments. The result of those benefits is more vigorous plant growth – as you can see from the roots in the lead image of this article.
At Costa Farms, we experienced the coir re-hydrating process firsthand. Dehydrated and condensed coconut coir arrives at the processing station and is placed in large pools of water, where it soaks back the moisture it lost. The resulting coir blocks are then shredded and stored until it it packed into Costa’s plantpots.
Since the world will most likely continue wanting their piña coladas and coconut curry and a typical coconut tree produces 50-100 coconuts a year, coir is a renewable resource. Add to that the fact that many plants do so well growing in the substance when compared to peat, and it seems like there is little downside to it. One not so desirable facet of the coir industry is that most of it is produced in India, so it often does need to be shipped far distances to reach its final destination. But given that peat also only grows in a few areas of the world and needs to be transported, we think coconut coir is a favorable alternative that also happens to produce healthier plants.