Tips for Using Coco Coir in Hydroponics

Coco coir is quickly becoming the most popular growing medium for use by hydroponic growers. Coir is an organic medium that offers excellent water and oxygen retention and provides for quality root structure and plant yields. It is also a great medium for people new to hydroponics, as it is similar to traditional soil and allows for hydroponic growing without having to buy a complete hydroponic system. However, coir does require special care and consideration to ensure healthy plants and root systems that produce high yields.

Hydrate and Wash Before Use

Coco coir is typically sold in compressed bricks. In order to use coir, it must first be hydrated. Follow the instructions on your package for the amount of water needed to hydrate. You will also need to wash your coir. 

One disadvantage to coir is that it contains a naturally high amount of salt, which can kill your plants. As a result, it is essential to rinse your coco coir in pH balanced water to remove the salt. Continue rinsing the coir until the tannins are washed out. Tannins will add a brown color to the water. When the water runs clear, the salt should also be completely rinsed. Some coir manufactures rinse and remove the salts before the final processing, so spending a little bit more on your coir can eliminate this step.

Coco Coir Requires Specific Nutrients

Coco coir is considered inert, or without nutrients, because it only has trace amounts of essential minerals. Coir does typically have high amounts of potassium and phosphorus, but because it only contains trace amounts of calcium, chlorine, copper, iron, magnesium, boron, manganese, nitrogen, and zinc, it often requires nutrient supplementation. 

Traditional hydroponic nutrient supplements contain high levels of potassium and phosphorus, which are not needed if you’re using coco coir. Instead, look for a coir-specific nutrient supplement or use individual supplements to create your own. The main nutrients you will need to supplement for are calcium and magnesium. In addition, coir is a great medium for microorganism growth but requires nitrogen, so your nutrient supplement should contain high nitrogen levels.

Increase Oxygen Levels

Because of the coarseness of coir fibers, it provides air pockets, making it an excellent oxygen source. Unfortunately, when you first rehydrate coir, it has a tendency to clump together. In order to release the air pockets and improve oxygen levels, it is essential that you get your hands dirty and break up any clumps to make your coir nice and fluffy before adding it to your hydroponic setup. Adding recycled glass stones or perlite can increase aeration levels as well.

Don’t Forget the Good Bacteria

One big advantage of coco coir is its natural ability to provide an ideal breeding ground for beneficial microorganisms, such as bacteria and fungi. Unfortunately, these microorganisms are not naturally found in the coco coir you receive. It is necessary for you to introduce these microorganisms into your system through supplements or organic nutrients and fertilizers. Enriching your soil with earthworm castings is another way to encourage microorganism growth.