I wanted to say how useful this morsel of information on coir was and to add my own experience of using it. I'm currently planting into a mix of very heavy clay and builder's rubble and thought I'd try to find some coir here in Greece. It came in 5 kilo blocks from a nursery in Athens. Though a little bulky, it was clean and easy to transport and store. Each block was then mixed with water. We used a large rubbish sack sitting in an old tree planter. If left to soak it broke down quickly to make about 50 litres of fibre. its good stuff, clean to work with and improves soil texture and water retention.
We then mixed the coir according to plant needs, with perlite (apparently Greece is one of its largest producers), manure (donkey/goat in our case and only available fresh so we have to be careful about using it round the roots of plants and be aware of its interesting range of grass and weed seeds), compost, gravel, some sand, schino homa - a type of compost/leaf mould found under the local mastic bushes, plus whatever soil we can find, to achieve soils suited to different plant needs. Whether or not the mixes are entirely successful, I will report back as the planting becomes more established. All the planting will be dressed with white gravel to provide a mulch, which we hope will retain moisture while acting as a weed suppressant.