What is Coco Coir & How to Use it in Hydroponic

Coco coir has been around for a while – gardeners back in the 19th century favored coco coir as a growing medium.

Although its popularity dipped for a while, the coco coir being produced today is of a much higher quality than it used to be, leading to more and more people once again looking into it as a way to grow healthier and more productive plants.

Here are our best recommended coco coir for your project:

What is Coco Coir & How to Use it in Hydroponic

What is Coco Coir?

Coco coir is a completely natural product. It looks similar to soil, but is actually made from the husks of the inner shells of coconuts.

The husks are soaked to loosen the coir, which are then dried in bales for at least a year. Once suitably dry, the coir is processed for use, with coco coir being well-suited to both hydroponics and outdoor gardening.

Pros & Cons of Coco Coir

What is Coco Coir & How to Use it in Hydroponic


  • When used as a growing medium, coco coir provides plenty of air pockets. This gives roots extra space to grow, which is why plants grown in coco coir usually have a much larger, stronger, and more expansive root system.
  • Plants grown in coco coir are usually much healthier and more productive.
  • Coco coir is great for retaining moisture – it can hold up to 5-9 times its weight in water.
  • Nutrient retention is also high with coco coir, giving your plants literally everything they need.
  • Coco coir is naturally high in lignin, a compound that is great for increasing beneficial microorganisms and protecting plants from soil-borne pathogens.
  • The decomposition process for coco coir is very slow, usually taking up to 20 years. This means that you will be able to reuse it several times, so long as you prep it properly before each subsequent use.
  • Coco coir has a neutral pH, so won’t interfere with anything else you’re using to achieve a specific pH level for your plants.
  • Due to the way in which it is processed, coco coir is completely sterile, so you don’t need to worry about bringing fungi or bacteria into your growing system.
  • It helps to deter garden pests due to its anti-fungal properties, which also helps to prevent diseases. Since coco coir doesn’t contain many nutrients, this also puts many pests off.
  • Coco coir is ideal for hydroponic systems because it’s so easy to use and doesn’t require as much monitoring as other growing mediums.
  • Coco coir is environmentally friendly and makes use of what would otherwise have been a waste product.


  • Coco coir can sometimes encourage vegetative growth over fruiting. This means that food-producing crops could end up with lots of leaves, but very little fruit. However, this can be rectified by adjusting how you fertilize.
  • Poor quality coco coir products can contain salt and chemicals.
  • It may be light and fluffy to begin with, but coco coir can actually easily become compacted.
  • Purchasing a pre-mixed coco coir product can be costly. However, this can be avoided by buying the individual components and making a mix yourself – something that is pretty easy to do.

Still don’t know what coco coir is? Take a look at this video:

Types of Coco Coir

There are a few types of coco coir, each one processed in a slightly different way. Each type can either be used on its own, or mixed with another for added benefits.

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Coco Coir Blocks

These bricks are coco coir in their most complete form. They are much less processed than the other types of coco coir out there.

Coir blocks may look hard and dry, but once you have soaked them, they will absorb the water and crumble down into a loose form of coco coir. Make sure that you use a large enough container when rehydrating coco coir bricks, as they can swell up to several times their original size.

Coco Coir Pith/Peat

With its rich texture and deep brown color, this is the coco coir type that looks most like soil or peat moss.

Coco pith is extremely dense. This means that it is great for holding on to moisture. However, when used on its own, it could provide conditions that are just too damp for the roots of a plant.

The main problem with coco pith is that some manufacturers don’t dry their products for long enough. This can mean that salts end up being released around the roots of your plant, which will quickly prove to be fatal.

Keep reading for tips on how to choose a high quality coco coir product.

What is Coco Coir & How to Use it in Hydroponic

Coco Coir Fibers

Coco coir fibers are quite stringy, which means that aeration is good when they are used as a growing medium.

However, unlike other types of coco coir, the fibers break down much faster, especially when exposed to large amounts of water. As they break down, the air pockets within them get smaller, which isn’t great for the roots of your plant.

Coco Coir Chips

Coco chips are basically a mix between coco pith and coco fibers.

With their large surface area, they’re great for absorbing and retaining moisture. Since they aren’t compacted, coco coir chips also provide plenty of air pockets for root systems to thrive.

Coco Coir Dust

Coco coir dust isn’t a mainstream product, but those who grow exotic plants will likely be familiar with it.

Coco coir dust is made from ground up coco coir fibers, resulting in particles that have a tiny surface area but are capable of retaining large amounts of moisture.

White Coir vs. Brown Coir

When browsing the stores for coco coir, you may notice two different colors; white and brown.

Both come from the same part of the coconut and both are processed in the same way. The main difference lies in the age of the fibers when they were harvested.

Since white coir comes from younger fibers, they aren’t as strong, but are very flexible. Although mature brown fibers lack this flexibility, they are much hardier, making them a better choice for growing.

How to Choose a High Quality Coco Coir

As mentioned above, not all coco coir is of the same quality – it all depends on how it’s produced and processed.

In addition to ensuring that your coco coir has been aged for long enough to prevent salts from leaching out, looking into how different manufacturers store their coco coir is a good idea too.

Due to its neutral pH, coco coir can quickly pick up pathogens, which happens quite frequently when stored in certain ways. In order to ensure that it’s safe for use in a garden, manufacturers spray the coir with chemicals. Not only will you want to avoid this if gardening organically, but the chemicals used can cause coco coir to decompose much faster than it usually would.

Don’t be tempted to pick a coco coir designed for ornamental purposes either. Yes, they may be much cheaper, but they contain large amounts of salt, which will be extremely detrimental to your plants.

Either do your own research before purchasing a specific brand of coco coir, or speak to your local garden center to see which products they would recommend.

What is Coco Coir & How to Use it in Hydroponic

How to Use Coco Coir in Hydroponics

Along with peat moss, coco coir is the most common hydroponic growing medium.

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Seasoned growers love its benefits, while those who are only just beginning to experiment with hydroponics find that coco coir makes the transition easy. It looks just like soil, and acts in a similar way, meaning that you can even use regular garden pots to set up a coco coir hydroponic system.

The simplest way to use coco coir in hydroponics is with the bucket system, although the wick system also works really well.

Either way, you’ll need to first prep your coco coir before using it in hydroponics. This is simple – all it requires is a good wash.

Even if you have purchased a high quality coco coir that has already been rinsed, it’s always worth doing it again to ensure that there isn’t any salt or chemical residue left behind. Hold your coco coir under running water until the water goes clear.

Once rinsed, you may find that your coco coir has started to clump up. Don’t worry, just break it apart with your hands and it will be ready for use. This is important because it releases all of those air pockets and ensures that oxygen is happily running through your coco coir.

Let’s find out the way to transplant Coco coir to Hydroponic through this video:

What Should You Mix Coco Coir With?

As great as coco coir may be, it can sometimes be better to mix it with another growing medium when using it hydroponically. The mixture you choose should depend on how you grow…

If your hydroponic setup makes use of a top-feed or an ebb-and-flow system, then perlite is what you need. Go for a 3:1 ratio of coco coir pith to perlite.

You could also opt to mix your perlite and coco coir 50/50, which can really boost productivity, but you will need to water your plants more frequently.

If your hydroponics setup leans towards deep water culture, then coco coir chips on their own will do you well.

Nutrients to Use with Coco Coir

Some sources of coco coir are pretty much void of all nutrients, while others contain minerals such as:

  • Zinc
  • Iron
  • Potassium
  • Copper
  • Manganese

However, these are present in very small amounts. They’re not enough to completely nourish your plants, but they will require you to adjust the level of nutrients you put into your hydroponic system.

You will find several pre-mixed nutrient blends out there specifically designed for use with coco coir. These contain extra magnesium and calcium, since coco coir usually holds on to these, but you need to also ensure that you’re providing an iron boost.

Coco coir binds to iron too, making this mineral unavailable to your plants. If your nutrient blend doesn’t contain any extra iron, you will need to add this in yourself.

What is Coco Coir & How to Use it in Hydroponic

How Often Should You Feed and Water Your Coco Coir?

Watering and feeding schedules vary hugely in hydroponics, especially since older plants will need more water than younger plants.

Some growing mediums will need to be watered a few times a day, while others need to be watered and fed on alternate days. Coco coir makes all of this much easier…

Typically, your coco coir hydroponics set up should be fed and watered once a day, although the smaller your containers, the more you will need to do this. Make sure that you continue watering until you have achieved a 10-20% runoff.

Ideally, your coco coir should always be between 95% to 100% saturated. If the coco coir at the top of your growing system feels dry, then chances are that more water is needed.

If you’re using a pot, lift it up to see how heavy it is. The lighter its weight, the drier your coco coir is.

How to Use Coco Coir in the Garden

While coco coir is especially useful to hydroponic growers, it has its uses in an outdoor garden too.

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Thanks to the way in which it provides plenty of aeration while still retaining moisture, coco coir is a fantastic soil additive. Clay soil lightens up when coco coir is added in, while sandy soil improves when it comes to moisture retention.

Either way, no matter your soil type, coco coir can significantly help with drainage and retaining water. A soil mix of up to 80% coco coir can be beneficial, just make sure that you hydrate and break up the coco coir before mixing it in with your soil.

You will have also likely noticed coco coir discs and pots. These are made from pure coco coir that has been pressed into various shapes to make them easier to use in the garden.

Coco coir discs and pots are most commonly used for starting seeds – the aeration that they provide encourages root growth and development in seedlings. Once the seedling has outgrown its coco coir pot, the pot can simply be planted into the ground or into a larger pot, since it will naturally biodegrade.

If you enjoy growing plants in terracotta pots, then you’re probably aware of how quickly the soil in those pots can dry out. Coco coir offers a solution – coir discs, or even a smaller coir pot, can be placed into a terracotta pot to increase water retention in the soil.

What is Coco Coir & How to Use it in Hydroponic

Peat Moss vs. Coco Coir

Just like coco coir, peat moss looks like soil and is loved for its ability to retain moisture, making it no surprise that the two are often compared.

When it comes to water retention, they both have unique advantages. While coco coir is able to retain more moisture than peat moss, it doesn’t hold on to water for quite as long.

However, the neutral pH level of coco coir means that it can be used as is to grow just about anything. On the other hand, peat moss is quite acidic, with a pH of between 3.5 – 4. Some plants will happily tolerate this, while others will need the pH to be raised in order to adequately grow.

Pests and diseases are another area where coco coir and peat moss differ. Coco coir is resistant to many pests, whereas peat moss not only attracts snails, but can also sometimes contaminate plants with fungal and bacterial spores.

For those concerned about their environmental impact, coco coir is definitely the more sustainable option. Coconut trees usually produce around 150 coconuts each year, providing a steady supply of raw materials to manufacture coco coir with.

On the other hand, a peat bog takes about 25 years to renew itself before it can be harvested again. This is why there has been a steady decline in peat bogs in recent years.

When it comes to cost, this varies depending on where in the world you are. Most peat moss is harvested from Canada, meaning that it is cheaper than coco coir in the USA. Since coco coir generally comes from Asia, it tends to be cheaper there than peat moss.


When it comes to the various growing mediums out there, coco coir is definitely one of the more promising options.

Not only will it provide your plants with just the right amount of moisture while aerating the soil around their roots, but it’s also sustainable, reusable, and helps to prevent pests. What more could a gardener ask for?

Last update on 2024-02-26 / Affiliate links / Images from Amazon Product Advertising API

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Jill Sandy

I am a sustainable focus gardener. I love decorating my home backyard with beautiful landscape design and creative garden care techniques I develop myself.