Cubed Tree Fern Nuggets for Orchids - Growing Media - 1 Pound Approximately 1"x1" Cubed Tree Fern Nuggets in a 1 bag. Tree fern has been used for decades by orchid growers who learned that it is a fast-drying, organic medium that was conducive to developing healthy orchid roots. Can be used alone or in combination with coconut husk chips, fir bark, charcoal or other orchid media. The tree fern's porous structure can provide excellent aeration around the roots and acts as a natural water reservoir. The size of the nuggets are perfect for medium- to large-sized orchids.