Cymbidium bark mix
As far as our own trials and results are concerned we will review our experiences, and Terry’s, separately as initially the tests were done in isolation of each other and without us knowing that Terry was experimenting with the same materials.
We began using the finely milled coir fibre product around five years ago. This is the material commonly available in briquettes in garden centres and supermarkets (NOT the briquettes with added fertiliser). The coir product was used to replace peat moss and rice hulls in our Cymbidium mix in a ratio of five parts bark, one part coir, and one part canunda shell. Results indicated that the coir lasted in good condition for two or three years and would have lasted longer.
Some three years ago we switched to a slightly coarser version of the product available in larger blocks at a more economical price, and around two years ago we began trialing the cocopeat/coir chips and fibre available in compressed blocks which make up 60 litres when reconstituted. This medium was trialed in a variety of mixes including as a sole medium, as a 50/50 mix with bark, and as a 70% cocopeat, 20% bark, 10% canunda shell mix.
This last mix being the one we settled on as the most successful under our growing conditions. It appeared to promote healthy root development, good plant growth, and appeared to avoid nitrogen draw down as sometimes happens with freshly potted cymbidiums in pine bark. This combination also allowed us to maintain our normal watering and fertilising regime as the plants were gradually moved across to the new mix following initial tests. All plants are watered overhead by an automatic system running on alternate days and once a week in winter. Feeding is via a top dressing of Dynamic Lifter at moderated rates and fortnightly with quarter strength liquid feed in summer with trace elements given as required.
One particular point we’ve noted using cocopeat is that the claims for water holding properties without creating an overly wet mix, seems to be accurate. If cocopeat chips are picked up a day after watering they feel damp but not soggy, but due to their make up a fair amount of water is held in their pithy structure and squeezing can release several drops of water from a single piece. In theory, the plant roots should be able to draw on this stored moisture effectively smoothing out the possible highs and lows of moisture availability between waterings. In terms of genera other then cymbidiums, we have moved all of our paphiopedilums into a mix of nine parts cocopeat to one part canunda shell. Following the reported results on the AnTec website, a few problem plants were trialed with such good results that all Paphs have how been moved into the new mix with encouraging results to date.