If you’ve recently read up on hydroponic gardening systems or browsed a gardening subreddit, you’ve seen the term “coconut coir” or “coco coir.”
But what is coco coir?
You couldn’t have stumbled onto a better guide!
Here are all the facts you should know about coco coir and why it’s important for hydroponic grow systems.
What Is Coco Coir?
A byproduct of coconut fiber, coco coir’s first use in gardening in the western world can be traced to the 19th century. But the coco coir used at the time was subpar and degraded quickly, so it fell out of favor. Coco made a comeback 100 years later as better production methods led to a hardier product.
It’s created using the fibrous threads found between a coconut’s interior and its outer husk. While both the coconut itself and outer husk were used for textiles and food, the coir was generally discarded.
Today, it’s compressed into bricks (to prevent mold and contamination) or sold loosely to the agriculture sector where it’s used as a growing medium.
Unlike its controversial counterpart, peat, coir is an environmentally sustainable product.
Coco coir can be mixed with small quantities of other mediums like Hydroton or perlite in a 90-95% coco coir blend or used as a standalone medium.
Pro Tip: Place the perlite or Hydroton at the bottom for better aeration.
When Should I Use Coco Coir?
If you’re getting into hydroponics, coco coir is an excellent growing medium for an easy, familiar transition. Because it functions similarly to potting soil, you can use regular pots for your hydroponics setup.
Coir also boasts better water absorption and air-holding capacity than Rockwool, making it vastly superior when it comes to more complex hydroponics setups.
Another factor you can’t ignore today is that coco coir is renewable while Rockwool is a non-biodegradable substance that will forever sit in a landfill.
5 Advantages of Coco Coir
If you’re thinking about giving coco coir a try, here are five great advantages it offers.
1. Makes transitioning from soil easy
Traditional soil and coco coir have several similarities, making it very easy for growers to move plants from soil potting to coco coir potting. Your hydroponic garden will look no different from a soil garden except for one difference: Instead of water, you’ll be watering the coco coir pots with a nutrient-rich solution.
2. Environmentally friendly
While peat moss is a perfectly suitable growing medium for plants, one can’t turn a blind eye to its effects on the environment. Coco coir is a repurposed byproduct that can be used many times over. Peat moss breaks down over time.
3. Natural insect repellent
Well, sort of. Most garden pests don’t enjoy coco coir as much as they do soil, offering an additional line of defense to your pest control system.
4. Hassle-free to set up and requires little maintenance
Traditional hydroponics can be a bit complex, especially to newbies. Coco coir doesn’t require much maintenance, making it suitable for newcomers and those with less time to spare.
5. Retains moisture
Coco coir is very effective at retaining water, providing plants with a good environment to grow. It can actually absorb up to 10 times its weight in water, so rest easy knowing your plants will never be dehydrated. There’s also a lot of growing room for roots to spread, which helps promote healthy root development.
3 Disadvantages of Coco Coir
Of course, not everything’s sunshine and roses. Coco coir has its share of limitations. Let’s take a look at three.
1. Costs can add up
Coco coir is often mixed with other media for better growth. This process of mixing can be annoying and time consuming. Manufacturers know this and have started to offer premade mixes. While this is great, these mixes can get pretty expensive. But if you don’t mind making your own mix, this shouldn’t bother you much.
2. Need for additional supplements
Your plant may require additional supplements. Plants grown in coco coir sometimes lack magnesium and calcium so “Cal-Mag” supplements may be necessary.
3. Must be rehydrated
Generally, coco coir is shipped in compressed, very dry bricks. The compression allows for smaller, lighter packages and reducing shipping costs, but it adds to your labor because you now have to rehydrate the bricks before you can use them. If I’m being honest, though, this is a minor negative and doesn’t require much effort.
2 Other Features (Pros or Cons? You Decide)
Some features of coco coir can be either an advantage or disadvantage depending on how you plan to use it.
It’s inert
Unlike soil, coco coir has no nutrients. That means you must control pH levels and provide hydroponic nutrients to your coco coir grow. Pouring a cup of water and calling it a day isn’t going to cut it here. While this certainly adds complexity, it allows you to build your nutrient profile from scratch for total control over your hydroponic system.
Hard to over-water
Coco coir can’t easily be over watered. It holds onto oxygen even if drenched, so if you’re a hand-water grower, coco coir will need additional effort. But if you’re a commercial grower, this may be a huge positive because you can connect automatic drip lines to plants.
Brown Coir vs White Coir: Does It Matter?
Two fibers make up coir: white and brown.
Wondering what the difference is?
White Coir
White coir is fiber from immature coconuts. They’re very flexible but are weak. Brown coir is made using fibers from mature coconuts and is stronger, albeit less flexible.
Brown Coir
Brown coir is the go-to option for the use of hydroponics because it is processed further after the initial harvesting. The biggest use of white coir is for rope manufacture.
Types of Coco Coir
When you purchase coconut coir, you are purchasing three components; coco chips, fiber, and pith (sometimes known as coconut peat). The three together offer a very powerful sustainable medium for grows. When picked apart, each of the three have their own distinct advantages.
Coco Fiber
Coco fiber holds less water but it has a higher air capacity.
As a rule of thumb, the more fiber you see in the mix, the more frequent your watering should be.
However, since it is mostly cellulose, fiber degrades fast. This affects the stability and reduces the air pockets over time.
To develop a well-structured and well-drained medium, it is important to achieve the right ratio of all three components.
Pith
Consider pith/coconut peat as the spongy component of coco coir. It has the appearance of tea leaves and can hold a high amount of water but this reduces the air capacity. Pith is very absorbent and decomposes much slower than coco fiber. If it is properly aged, it develops into a substance that can hold sodium and potassium until fertilization. A stronger ion like calcium can then kick the sodium and potassium out, thus locking the calcium in place and removing harmful salts. Therefore, proper aging of pith is vital. Unfortunately, this process can take about four months, reducing the time available for use.
Coco Chips
Of all the three, coco chips hold the least amount of water. You could consider them as a natural alternative to clay pebbles. Coco chips have a higher air capacity when holding water – they actually have the greatest water to air ratio.
Our 3 Favorite Types of Coco Coir
By now you should know what coco coir is, how it is manufactured, the different types, and what to look for when purchasing.
Armed with that, you can choose the right product. We’ve done the heavy lifting for you – check out our findings below.
FoxFarms Bush Doctor Coco Loco
| At A Glance | Triple washed to minimize salt content; lower humidity reduces risks of mold and rot. |
| More Info | Read more on Amazon → |
FoxFarm’s Coco Loco potting mix behaves like small sponges, making water easily available to your plants as needd. It can hold more than its weight in water but still drains very well. FoxFarm claims the potting mix has a lower humidity that reduces the risk of mold, root rot, or insects bothering the plant.
Available Sizes: 2 cubic feet, 27 cubic feet, 55 cubic feet
General Hydroponics CocoTek Premium Coco Growing Media
| At A Glance | 3 varieties of coco coir and has low sodium content |
| More Info | Read more on Amazon → |
This high-quality growing medium from General Hydroponics is a sustainable substitute that can be used alone or blended with other mediums like perlite, Hydroton clay pellets, or topsoil. It also features very low sodium levels and is available in three variations.
- CocoTek Premium Coir (1.5 cubic feet): Contains coconut coir. Can be used alone or blended with other media to create different mixes.
- CocoTek PX (1.5 cubic feet): Premixed perlite and coconut coir. Provides optimum moisture retention and aeration. Ready for use out of the bag.
- Natural Coconut Coir Black (5 kg compressed block): Compressed coir block. Rapidly expands when hydrated.
Hydrofarm GROW!T Coco Croutons
| At A Glance | Organic substitute for clay pellets, rinsed in fresh water, ready for use. |
| More Info | Read more on Amazon → |
These lightweight, OMRI-listed coco croutons from Hydrofarm are a perfect organic substitute for rocks or clay pellets. They’re washed with fresh water and come ready for use out of the bag.
Another interesting feature of the croutons is their porous structure, which allows for easy root penetration. They have a similar water capacity to clay pellets. This bag comes in a 28L size.
Which Coco Coir Brands Are Best?
FoxFarm and General Hydroponics are some of the oldest plant nutrient companies. They’ve been in business for close to 40 years and you can’t really go wrong with either option. Both companies offer a range of related plant nutrient products that are intended to work in tandem with their coco coir products to boost your plant’s growth.
FoxFarm is known for their tight control over the production process and, rest assured, you’ll receive well-aged, dry coco coir that’s flushed of salt. They are, however, much pricier than their competitors
Check out our FoxFarm Nutrients Review for more information on this industry-leading brand.
If budget is an issue, General Hydroponics can be a solid alternative. With low sodium levels, you won’t have to flush too much salt out, making it suitable for first-time growers.
Hydrofarm is among the largest distributors of hydroponic equipment and has been in business for more than 40 years. They focus on delivering premium quality products but prices tend to be reasonable. However, Hydrofarm is solely a wholesale business that doesn’t deal with customers. If you face any issues, you’re stuck dealing with your third party supplier.
What Is Coco Coir? Final Thoughts
Coco coir is an attractive alternative to traditional soil and a popular growing medium for hydroponic systems.
If you’re ready to give coco coir a go, here are some dos and don’ts.
- DO hydrate the bale, block, or brick by soaking it in water for at least 15 minutes before use.
- DO use a large enough container for hydration. Coir expands 5-7x in volume. For bale, use an outdoor trash can or small swimming pool. For bricks, drywall buckets would work.
- DON’T use bricks that aren’t absorbing water or expanding.
- DON’T attempt to slice a brick of coir in half. Even a chainsaw would fail at the task.
- DON’T throw away excess coir. Coir can be stored for years while still retaining its properties.
Would you use coco coir for your next hydroponics system? Let us know in the comments below!