Singing in the Coir: Mattins

This is the first in a short series of posts I’ve meant to publish for some time. A lot of some time. I wrote the first version in 2014! Way back then I’d been largely peat-free for five years. So, in 2019, I’ve been largely peat-free for ten years. I have to say “largely” because, for practical and financial reasons, I cannot guarantee that a plant I buy in hasn’t been introduced to peat at all. But I can guarantee that any compost I use to pot on is peat free and, apart from any peat already around the roots of things I shove in the ground, I never add peat to my soil. Nor to any of the raised beds I’ve built over the years.

For now, I’m going to concentrate on introducing you to what I think is the most versatile peat-free compost – coir.

Many moons ago (that’s many ago before 2014), when I was but a slip of a lad (well a lot thinner anyway), a chap on the telly by the name of Geoff Hamilton introduced me to something called “coir.” Unlike a certain modern-day presenter, he didn’t preach but merely highlighted environmental things in an interesting way that made me want to find out more. And so I researched. It wasn’t easy in those days because coir was a relative newcomer to the gardening scene, having previously been used only to make things like doormats.

I should have got a bigger greenhouse! But everything in this photo is (or was – it’s an old photo) growing in coir. And growing well.

But I soon found that young plants grew a lot better in coir. I also found out that coir wasn’t cheap back then! Today, it’s comparatively cheaper. OK, pricier than the “three bags for a tenner” stuff – you gets what you pays for and cheap compost is just that. Cheap! But coir is comparable price-wise with a lot of the better composts, peat-inclusive or peat-free, you can get today.

I buy my coir as large blocks – “bales” they’re called – which, when re-hydrated, make about 70 litres of compost for about the same as a bag of decent compost and certainly cheaper than a lot of the niche peat-free bags you can get.

Don’t get me wrong. SylvaGrow is brilliant peat-free compost but when you factor in the environmental cost (and petrol) of a day’s round trip to get it, it’s just not feasible for me, here in not-in-England South Wales. Dalefoot compost is good quality-wise but at £10.99 for a 30 litre bag it’s eeek! If I were to order 20 bags on a pallet it’s cheaper per bag at £9.50 but add the £20 delivery charge and you’re still talking about £210 for 600 litres of compost. And do you want 600 litres of compost in one go? For me, coir works out at around £6.25, delivered, for 70 litres.

So What is Coir and What is its Environmental Impact?

Coir is a natural waste product. A lot of it comes from Sri Lanka. It’s a by-product of the coconut harvest which would otherwise go largely to waste. Coconut husks, ground up and dehydrated, compressed and shipped. Some people go on about the shipping overhead. All the way from Sri Lanka in a ship. But think about the volume a bale takes up. We’re talking light, dry, compressed here. No water. You can probably ship a lot more coir from Sri Lanka than you can peat from Ireland for a given environmental overhead. My coir bales come in 4-packs. So around 280 litres of compost. I can (I have) carried two 4-packs around in one go. Try carrying eight 70 litre bags of compost at once.

And if you’re that worried about the coconut shipping overhead you’ll never eat a Bounty bar, right? Nor a coconut cake ………!

Coir re-wets easily. We’ve all done it – forgotten to water the pots in the greenhouse. And once normal composts dry, they crust and when you try and water your pots, the water runs off the top of the compost and down the insides of the pot and straight out of the bottom. This won’t happen with coir.  It has good water retention properties yet will also drain easily so it’s pretty hard to seriously over-wet it. It has a neutral-ish pH, generally around 5-6. It’s sterile and you need to add fertiliser but this means that you can decide which, and control the amount of, fertiliser you use.

When it gets here, it’s processed into a range of products. Doormats, cushion fillings and other stuff. And compost. As compost it has a number of guises. You’ll find it sold in bags of seed compost (with added vermiculite and stuff, all organic), potting compost (with added organic feeds and stuff), capsules (like those Jiffy peat things but without the peat) which fit into trays and get re-hydrated so you can sow a seed in them. Wow expensive! It’s in a lot of peat-free composts. And finally you can get it as compressed bricks or bales of pure coir. A brick is about the size of (wait for it) a house brick and will hydrate to produce about 9 litres of compost. A bale is about a foot square and six inches thick and will re-hydrate to produce about 70 litres of compost. A dry bale weighs about 5Kg. About the same as resident cat.

As I’ve mentioned, coir is sterile. Completely sterile. So you won’t find any stowaway weed seeds or unexpected chemicals. I actually think the lack of nutrients is a bonus as I put on my pointy hat and get out my cauldron on a stormy night to process the slow worm tails, mouse gizzards and other easy-to-find ingredients, collected by aforementioned resident cat, and prepare my secret feeding potions, custom-brewed to suit each plant, it’s state of growth and so on. And you don’t need to worry about having different composts for plants that really need a low pH (just add an ericaceous feed) or lime-lovers (just don’t).


If you buy bales, a 4-pack is about a foot square and two feet high. It’s a solid shape. I stack them, quite stably, two 4-packs high. So a square foot of floor space. Compare to the space you’ll need for eight bags of compost from the garden centre. And remember the fun of lugging them around.

Bags of compost have a shelf life. You need to use them within one season or the compost will go stale. And that’s forgetting that they’ve probably been stored outside at the garden centre in the British rain. And the rain will have washed some (or a lot) of the nutrients out of the compost. And if the bag is wet, it’s a lot heavier to lug around. You can happily store a bale of coir for years without it deteriorating. You add nutrients at the re-hydration stage, at which point the resulting compost is as fresh as fresh can be. Of course, once re-hydrated, you should treat coir the same as ordinary compost – use it within a season.


That’s the introduction to coir. Tune back in next week, same time, for instalment two, in which I’ll blab on about coir buying-options. Instalment three will cover how I use coir and the successes I achieve, or don’t. I’m being honest here! But I hope to convince you, dear reader, that it’s worth giving it a go.


5 thoughts on “Singing in the Coir: Mattins

  1. As soon as you mentioned the great Geoff I was with you. But then I would have been with you anyway, peat free is the only way to my mind. Very informative. Very good. 🙂

    1. I find that many people are wary of coir to begin with. But it’s a no brainer once you get going.

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