why coco coir?

Sustainability:
The main reason behind choosing coco coir as a growing medium for many growers is because it is a renewable resource. In general, coconut trees are capable of generating as many as 150 coconuts per year. Coco coir is a byproduct of the otherwise discarded husks of coconuts from annual harvests.

High Water Retention:
Coco coir retains high amounts of water; capable of holding up to 10 times its weight in water. Yet because coco is hydrophilic, the medium retains plenty of air space for your roots at a ration of 70/30 water to air when watered to run off. This property also allows for growers to use high-yield grow styles like drain to waste where plants are fertigated daily.

Low Nutrient Retention:
Coco coir has a high CEC (Cation Exchange Rate) meaning it will not hold on to most nutrients, keeping them readily available for plant uptake. Coco coir does tend to hold on to Calcium (Ca), Magnesium (Mg), and iron (Fe) so some growers opt to add those elements on top of their base nutrient program OR use a coco-specific nutrient line like Canna Coco A/B(link. With daily watering to ample runoff (20% – 25%), some growers are able to reduce the requirements for additional Ca, Mg, and Fe entirely! Your author is one of those growers.

Faster Growth:
Coco isn't compact, unlike soil, so your plants' roots have free reign to grow, and tend to grow a lot faster; nutrient absorption is also sped up. This makes for bigger plants in the same pot, so if you don't have much space, you can place more, smaller pots. Coco growers can often achieve similar or better results than soil growers using 5x the pot size by utilizing high frequency fertigation.

Reusable medium: 
When properly treated, coco coir can be reused. It’s durable, but you need to make sure you prep it correctly for the next growth cycle to guarantee a healthy grow cycle. That said, it’s also affordable. I find it a better use of time to purchase fresh coco for each run and amend your gardens with the used coir.