|| HOME |||Galuku >>|
Text by Terry Poulton and Rob & Noe Smith
Coconut Husk (Cocopeat)
An Alternative Potting Medium
For many years, pine bark has been the mainstay when it comes to potting mediums for most orchids in Australia, particularly for Cymbidiums. Used either as a sole ingredient, or in combination with other materials such as peat moss, perlite, isolite, rice hulls, peanut shells, etcetera, it has provided a stable medium suitable for most growing conditions and cultural regimes. Pine bark has provided orchid growers with a reliable and commonly available medium as it is a by-product of a long-term sustainable industry in this country. Bark has numerous advantages and a few disadvantages, but, on the whole, bark, particularly composted bark, has proven to be a convenient and reasonably cost effective medium for most genera.
This article is essentially intended as an introduction to a less well-known product now becoming more widely available in forms suitable for orchid culture – cocopeat or coconut husk. Trials and experiences both here and overseas indicate that it can provide a direct alternative to pine bark, or make a compatible addition to it as part of a more complex potting mix. Some commercial growers here and overseas have moved past trials to sustained use of this product.
In this article we have combined our own experiences trialing cocopeat in various forms with results achieved by others, including commercial orchid nurseries both here and in the USA, and with data from Australian and American distributors of the product. Hopefully in this way we can provide a comprehensive view of the material and its suitability as a potting medium for Cymbidiums and other orchid genera.
Some background information on the material and its production is appropriate, with the following information being sourced from both Australian and American suppliers (in this case, Galuku Cocopeat Australia and Sai Coir USA; anyone wishing to check out their comprehensive websites can go to www.cocopeat.com.au for Galuku, or www.saicocopeat.com for Sai Coir).
The product is made from essentially waste material generated by coconut farming in India and Sri Lanka, where some ten billion coconuts are produced each year. The thick fibrous husk (removed from the coconut as we know them in the shops) is made up of long fibres and sponge-like pith. We all know the most common products made from this material for many years – coir door mats and coir pot liners for hanging baskets – both made from the long tough fibres of the coconut's husk. Only around 20% of the husk is used for coir fibre extraction and is stored in large piles from two to four years, during which time it is weathered and leaching takes place. The next step in the process sees the long fibres removed, after which the product is dried in large concrete yards. A second screening removes short fibres prior to the material being compressed in hydraulic presses. The resultant blocks are tested for pH levels, salinity and any contaminants prior to storage and shipping.
The claimed properties for coir/cocopeat are high moisture retention, long-lasting (up to five years is claimed), that the moisture held is released slowly, good drainage, an ideal natural pH, that it is easy to re-wet, contains no weed seeds and is cost-effective and recyclable.
|| HOME |||Galuku >>|