As our premium bark has undergone a 21 day treatment during which the pH is adjusted, fines are washed away and more, you can use it with confidence straight from the bag, just flush well initially after repotting.
Bark forms the basis of the ideal growing medium for Phalaenopsis, Oncidium, Laelia, Cattleya and Dendrobium orchids.
The time to think about repotting your orchids is immediately after they are done blooming. First you need to do the following checks:
Check whether the roots are crowding the container
Are the roots growing over the edge of the container
The medium has broken down and usually emits a sour odour (Pine bark usually takes around 2 - 3 years to do this depending on how it was watered and fertilized)
If you see any or all of the above happening then you can repot. The best time would be when you observe renewed root development for example from the base of new growth. If the plant still has flower buds but the plant is in poor condition then it is advisable to remove these buds before repotting as they will only serve to weaken the plant further.
Use medium pine nuggets (7-20mm) pieces for younger plants and larger pine chips (30-50mm) for the larger more mature species. Use a clear container if you would like to observe the roots as aid for you to know when to water.
You can combine bark with sphagnum moss for additional water retention or use Hyuga Pumice for good water retention but superior maintenance of the media structure. Add roughly 5% agricultural charcoal (which is NOT the same as braai charcoal which has been treated with many different chemicals).