Orchiata Orchid Bark - Power Plus 1/2 - 3/4 Inch. 1/4 Cubic Foot Bag Orchiata - Power Plus. 1/2 - 3/4 inch. 12 - 18 mm chips. plus/minus Popular all around general purpose orchid potting medium. Orchiata is a unique, stable substrate designed to be used straight from the bag for potting and re-potting orchids. 100% pure New Zealand Pinus radiata bark, sourced from renewable, man-made forests. Jim's orchid supplies offers a wide variety of orchid growing supplies including quality orchid potting mediums: