Stag horn ferns (Platycerium) are air plants that are native to the tropical and subtropical regions of North and South America, Southeast Asia, the Philippines, Indonesia, Africa and Australia. Stag horn ferns get most of their nutrients from the air, growing on but not feeding on tree trunks and branches. You can grow stag horn ferns indoors mounted on a hardwood board, or outdoors mounted directly onto a tree, if you live in a warm, humid climate where the winter temperatures are mild and non-freezing.
Mount the stag horn fern by placing the lower fronds on top of a pile of sphagnum moss on top of a hardwood board that is wider than the lower basal fronds. Tie the fern to the board using fishing line, ensuring that the bud is just above the moss.
Allow your stag horn ferns to receive bright, indirect sunlight. Hang the board in a location with dappled shade. If the stag horn ferns are exposed to any direct sunlight, ensure that it's only early morning sun.
Water your stag horn ferns once every week, soaking the moss with distilled water or rainwater. Pour the water over the moss until it becomes thoroughly moistened.
Feed your stag horn ferns an organic fertilizer, such as a fish emulsion, according to the dosage instructions on the package. Provide the fertilizer once each month during the spring, summer and early fall.
Remount the stag horn ferns onto a larger board when they outgrow the original board and the basal fronds become wider than the board.