Product Review: Fair Trade Coir Compost

I've been trialling some Fair Trade coir compost lately to see how it performs. As you can see it's different to most other growing media because it comes in a block and needs to be added to water before it can be used. This is quite easy buts needs some thought beforehand.

The block is a bit larger than a house brick and looks a little like a large chocolate brownie when it comes out of its wrapper. This has clear instructions, though if you lose it you'll need to go onto the sales website if you've forgotten what needs to be done.

According to the website the block weighs around 650g - mine was just over 800g. About 6 litres of water is needed to reconstitute the coir to yield approximately 9 litres of compost. The instructions say this can take up to 24 hours, but I found by using tepid water and vigorous stirring from time to time, it can be done in around an hour. The key is to ensure the compost is evenly wetted through before using.

I used the coir as it is to pot up some garlic, so it has a chance to be frosted this week prior to planting out on the allotment when it (the allotment, not the garlic) has dried out. There was just enough to pot up the fattest cloves from my two bulbs of solent wight garlic. Under other circumstances, such as potting up plants in a container for the season, I'd mix the coir with my own sieved compost plus some grit, or with a peat-free multi compost. This is because the coir is low in nutrients and wouldn't be sufficient to keep the plants going for a long period.

I have quite a few thoughts about the coir as follows:

  • Lightweight - it's easy to pick up and carry around
  • Relatively small - doesn't take up much space for storage
  • Reuse - it uses up a resource which would otherwise go to waste as it's a by-product of the coconut industry
  • Reduced packaging - which can also be composted afterwards
  • Ethical - enabling a community in Sri Lanka to to have a better standard of living
  • Holds water well, once rewetted -  reduces the need for watering
  • A different growing medium - it's new to most people and has different growing characteristics to what they're used to. Information on how to use it effectively is hard to find
  • Not usable immediately - gardeners need to anticipate using it, rather than just reaching for a bag
  • Top of compost dries out quickly - thus giving a false impression of actual watering needs. Users need to scrape below the surface to see if the rest of the compost is wet or dry
  • Relatively low nutrient levels - only really suitable for quick growing needs e.g. seedling potting up or as a component of potting mixes in the longer term. NB most other growing media options have fertilisers added to extend the growing life of the product
  • Availability - not usually found in the garden retail isles of supermarkets, garden centres etc., but instead it's available from Oxfam and other retailers selling Fair Trade products. Therefore, most gardeners will have to seek it out, rather than it forming part of their usual shopping routine/visits. NB it is available online and can be p&p free if ordered in sufficient quantities
  • Cost - it's around £2.50 for one 'brick' which makes it the equivalent around £12.50 for 50 litres of compost (the usual size for bagged products, though to be fair these aren't 100% coir). 
The jury's out on...
  • Sustainability - how much does its transportation from Sri Lanka counterbalance the reuse, less packaging and ethical plus points listed above?
  • Product size - it's a suitable amount for a small job, such as potting up a few seedlings, but a couple or more packets would be needed for most tasks. If there are leftovers, these have to be stored somehow (as it's not in a handy bag), or dug into the soil somewhere as an improver (though the latter option is a good use of the product)
Overall verdict

This is useful to have as a standby when you need some growing media and the shops are shut or you can't get there for a while. Unreconstituted it takes up much less storage space than its bagged up counterparts, so it's easy to keep a couple of 'bricks' in the garden shed or garage for use when needed. Relative costs can be kept down if it's used as a component in home-made potting composts, rather than as a 1:1 replacement for bagged growing media. 

The Fair Trade industry needs to look further at awareness and supply options if this product is going to take off as a suitable choice for gardeners. I believe most of them will not be looking to Fair Trade retailers such as Oxfam, or online for the purchase of these gardening materials. 

Judging by the comments I've seen in a couple of forums, ordinary gardeners like me need much more information available on how to use coir effectively. Watering and nutrient problems are often cited as reasons for poor performance and why the product isn't used again. Gardeners need to understand how coir differs to the multi-purpose products they're used to and how it can be used in home-made compost mixes. In the latter case, the popularity of ready mixed bagged products means many gardeners no longer have the know how. NB these final remarks don't just apply to the product under review for this post, but to most of the new reduced peat or peat-free products coming to market. In my experience these products don't have much information on their labels advising gardeners on how to use them effectively.

The most useful online article I've found so far which plugs this knowledge gap is this one by Monty Don from 2002 (see the coir information about half way down and a suggested potting mix using coir at the end).

Related article: Compost mixes made and used at Holt Farm.

Disclosure: I received a product sample for independent review purposes. 


  1. Thank you for your review. I have seen it but never tried it!

  2. The coir I use for seed starting comes in a brick like this. It's really easy to hydrate if you use REALLY hot water. I'll microwave a cup of water for a couple of minutes and then pour half of it into a container holding the dry coir brick. It will almost immediately start to expand. Then I'll flip it over so that the dry side is flat on the container and pour the other half of the cup of water into the container and let it absorb the water. Completely hydrated and aromatic in a couple of minutes.

  3. Really useful review. I have problems judging watering of seedlings at the best of times, so I've tended to steer clear of coir based composts, but you make a good point on the storage advantages. For me the issue is one of cost. Until peat free composts are closer in price to and as readily available as the peat based composts it will remain a middle class lifestyle choice. I've yet to find peat free compost locally, and delivery costs are eye-watering for on line delivery.

  4. Clint - will you give it a go?

    MTB - I'll remember that for next time, thanks for the tip :)

    Janet - I read in 'The Garden' a couple of months ago that last summer's poor weather affected the peat harvesting, so the price difference between peat/non-peat growing media is poised to get closer. I think Karen has remarked on the poorer choice of this kind of thing in Wales before...


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