Coir Substrates

Our goal? To make a positive difference. It therefore comes as no surprise that growers all over the world have become convinced of the added value of our coco substrate. After all, it’s the most sustainable growing medium for vegetables, soft fruit, flowers and plants. But there’s more! By investing in the countries that produce coconuts, we help local communities build a better future.

What can we do with coco pith? And how can this residual product help us make the world a better place? In 1984, these questions marked the start of Dutch Plantin’s journey. They conducted a few practical experiments with rose growers, using coco as a growing medium. They hit the ground running and less than a year later, their first factory opened its doors. Meanwhile, Dutch Plantin has fifteen modern production sites in Asia, Africa, and The Netherlands. They employ over 1,500 people and supply their products virtually across the globe.

Whether it’s vegetables, soft fruit, flowers or plants, the same things come first for professional growers worldwide: a strong cultivation and an optimal crop yield. It is not a coincidence that more and more cultivators discover the unique properties of coco substrate. Our 100% organic products are stable and ensure fast and good rooting, and strong plants. Besides, our growbags, blocks and briquettes are easy to irrigate and require far less fertilisers.

A coconut becomes a growbag or a block to grow blueberries, tomatoes, roses and much more. You would almost forget this growing medium once grew on a tree itself. We have an innovative production process that allows us to stabilise the coco pith in a unique manner.

Growbags

slabs and open-top bags

Blocks and Briquettes

for planters, gutters and pots

Retail
Products

FAQ

How stable is coconut as a growth medium?

In our first experiences using coco pith as a growing medium, we approached rose growers. It takes about five years for roses to grow. Coco pith may be an organic material, but our coco still proved incredibly stable. Five years on, the structure had hardly changed.

How do I recognise unstable coco?

They colour may give you an initial indication, but it is only during the cultivation that you will find out whether or not the material is stable enough. Is the coco becoming darker and finer in cultivation? That means it is less aerated, causing the product to collapse. Unstable coco chips also present a decrease in volume and air percentage. At Dutch Plantin, we do our utmost to prevent this.

Why are there different growbags?
Our growbags can be used to grow any type of vegetable, flower and soft fruit. Crops that require a lot of water and are cultivated in warm regions require a finer mixture to prevent unnecessary draining or water evaporation.
In colder regions, mixtures with better draining properties are used. It is important that they enable optimum drainage without creating air deficiency. The plant root needs water, air and nutrients. In the bottom layer of the growing medium, where the most active roots are, good drainage properties are particularly important. Our growbags are available in various sizes. To find out which growbag best suits your crops, contact us and we will gladly advise you.
What are the differences in fiber?
Fiber has been used for centuries for products such as brooms, ropes, mats and filters. It goes without saying that the requirements differ for fiber used as an additive in potting mixtures. Therefore beware of coco (to be used as an additive) that does not have the correct thickness or length, or that does not have a guaranteed E.C. value, i.e. salt. Dutch Plantin’s fiber is specially produced for the horticultural sector and we guarantee stable quality.
What is washing and buffering of coco?
Coconuts often grow in regions where the subsoil is high in salts. Think of those classic holiday postcards with large palm trees on golden beaches… As a result, coconuts can easily tolerate and absorb potassium, sodium and chloride, unlike most plants that are cultivated in the horticultural sector.
These salts are present in the whole plant and it is therefore a minimum requirement to wash the part of the plant we are going to use, in our case the husk, to bring the E.C. level – the salt – down to an acceptable level. If we didn’t do this, growers would have to wash the coco, because apart from the high sodium and chloride levels, it would also contain too much potassium, which is an antagonist for calcium and magnesium.
Washing the coco doesn’t solve the entire problem. Coco has a negatively charged complex, surrounded by a couple of positively charged ions: sodium and potassium. Since these elements ‘stick’ to the complex (like iron to a magnet), initially there is no danger to the plant root because the sodium and potassium are not available. The problem starts when fertilising with calcium, for example. The calcium will push the potassium and sodium aside and take their position. Consequently, the calcium that is connected to the complex won’t be available to the plant, while sodium and potassium that are released into the soil moisture will become available. Strawberries and young plants are particularly sensitive to this.
To avoid this ‘time bomb’ problem we offer buffered coco pith. In buffered coco pith, the ion exchange, as we call the process where calcium pushes the other ions off the complex, has already taken place and other salts, such as sodium and potassium, have been washed away.
If you use washed or unwashed coco, you might therefore need to top up with extra calcium.
What is the difference between a brown and a green husk?
When the coconut is harvested, its outer husk is still green. This husk is peeled off the inner nut and in many cases it just remains on the coconut plantation for years. Only a small percentage is used to produce coco pith, fiber and coco chips. Some companies use the fresh green husk to produce substrates because it is easier to process. Dutch Plantin prefers the older, woodier and therefore more stable brown husk. The coco pith products made from these older husks are therefore more stable too.
What is the effect of fiber in growbags?

We know that fiber carries water through the substrate thanks to its capillary action. As a result, water is absorbed more easily, but it also drains more easily. Excessively short fiber loses its function and excessively long fiber cannot be processed. We also know that fiber makes the substrate more elastic by improving the structure of the growbags. However, in longer cultures, this might turn against you. Coco pith and fiber
contain lignin and cellulose. Lignin is woody and therefore hard, while cellulose is a soft material. Compared to coco pith, fiber contains more cellulose and less lignin. This means that fiber decomposes faster than coco pith. How fast it will decompose depends on the growth circumstances and on the thickness of the fiber. Thicker fiber has a smaller surface per weight and breaks down more slowly.
As a result, fiber no longer has a positive effect on crops like roses after a few years. It only has a short-term effect (one to two years). Therefore, Dutch Plantin advises a 1/4-inch sieved material for longer cultivations, which seems finer but has a more stable air content than less sieved material (1/2 inch or even 3/4 inch).

Some companies steam coco. Why does Dutch Plantin not do this?
Some companies steam coco to eliminate weeds during the cultivation process.
Dutch Plantin conducted research into the effects of steaming on the coco structure which reconfirmed that the structure of coco deteriorates when it is steamed.
To preserve the unique properties of coco, Dutch Plantin opts for strict monitoring of the raw materials and a clean production environment, so steaming is not necessary.
Is there enough coco available?
This is a hot topic, also in the peat industry. Dutch Plantin can confidently confirm that there are enough raw materials available for the coco products used in the horticultural sector. We have conducted a study into the availability of coco which shows there are an estimated 9,600,000 ha of coconut plantations in the world. If we presume that each hectare has 150 trees, which yield 75 coconuts each per year, then we will have enough raw materials for nearly 6.5 million tonnes of coco pith a year.
However, the availability of raw materials doesn’t necessarily mean that there is enough coco available for professional horticulture. Given the strict requirements our products need to meet, not just any production process will do. That is why Dutch Plantin is proud of its fifteen production sites spread across Asia, Africa and The Netherlands, where we carefully produce coco products that can safely be used.
Why are the Dutch Plantin production sites far away from the sea?
Coconut palm trees often grow in soil that is high in salt. Think of those classic holiday postcards with large palm trees on golden beaches… Coconuts can easily tolerate and absorb potassium, sodium and chloride. Unlike most plants that are cultivated in the horticultural sector, these salts have no negative impact on palm trees. During our production process we wash the plant to reduce the salt levels to an acceptable level. Failure to do so would entail more work for the growers, as they would have to wash the coco to get rid of the excess levels of sodium and chloride, and to counter the fact that potassium is an antagonist for calcium and magnesium.

Dutch Plantin produces coco pith from the husks of coconuts that grow on palm trees located far away from the sea. These trees benefit from vast amounts of rain during the monsoon season and therefore grow in soil with a reduced salt content. As a result, the raw materials for Dutch Plantin’s coco pith are significantly lower in salt. Moreover, the salt can easily be washed out, which considerably reduces the cost of rinsing.
Higher transportation costs to the harbours are of secondary importance to Dutch Plantin compared to our long-term vision: growers receive a safe product made with the highest-quality coco. Based on their years of experience, our specialists strategically choose long-term production locations, guaranteeing the best quality, today and tomorrow.

From coconut to fertile growing medium

When you see our growbags, blocks and briquettes, you would almost forget these substrates once grew on trees themselves. How does a coconut become a fertile growing medium? This required an innovative production process. Dutch Plantin carries out this process in-house, from a to z. For all our products, the starting point is the husk of the coconut, also known as the shell. By processing it in different ways, we produce three raw materials: pith, fibres and chips.

COCONUT PITH
To produce pith, we remove the fibres from the husks. The aging process starts immediately afterwards, this stabilises the pith. It involves storing the product for at least four months in bunkers. Once this process has been completed, we sift and wash the pith to remove any remaining fibres. Then, our innovative buffering process begins. The salt level is reduced and we add calcium. This is done to remove monovalent positive ions such as potassium, and water-soluble elements such as sodium and chloride. The result? Even after years of using the substrate, the structure and the correct water-air ratio remain intact. After buffering, we fill the growbags or press the pith into blocks and briquettes.
COCONUT FIBRES
Dutch Plantin uses the entire husk. Which makes sense: even the fibres we remove for the pith are very useful. They improve the moisture transport. To do so, they must meet very strict requirements regarding, for example, salt levels and length. Even thickness is important, because fibres that are too thin decompose too fast. In our factories, the fibres are carefully sorted based on quality, cut to size, and then washed, dried and pressed.
COCONUT CHIPS
We don’t splice all husks into fibres and pith. Some of the shells are shredded. This is how we get coconut chips: the ideal additive for potting soil mixtures. The chips retain water, aerate the potting soil and mix perfectly with, for example, peat, turf, clay granules or perlite. Like the other products, the chips are also subject to the careful process of cutting, washing, buffering, drying and pressing.

From coconut to growing medium in a minute and a half

Curious to know how the production process – from the coconut plantations in India and Africa to the final products for growers worldwide – works? Watch the video.

Houweling-Dutch Plantin