Leatherleaf Fern, also known as Leather Fern or Seven Week Fern, can tolerate a range of growing conditions, including coastal climates. Leatherleaf Fern is best in fertile, evenly moist, well-drained soil in partial to full shade and grows fast in optimum conditions. More tolerant of some sun, lower humidity, and drier soil than most ferns, plant outdoors in a location that has filtered light, especially during the hottest part of the day. Temperature, light intensity, soil moisture, and humidity, all contribute to the stress or success of your fern.
After planting your Leatherleaf Fern, water deeply and regularly for several weeks to reduce plant stress and facilitate root development. After roots have become established, reduce frequency and water as needed to maintain even soil moisture. The amount of water required is dependent on several environmental factors such as wind, temperature, soil type, and light intensity. Leatherleaf Fern is tolerant of irregular watering schedules. Apply a layer of mulch to help retain soil moisture.
Pruning is not necessary, but any dead or damaged fronds can be removed at the base to improve the plant's appearance.
Rumohra adiantiformis is a semi-hardy fern, hardy to 25-30°F suited for USDA growing zones 9-11. Cold temperatures may result in leaf burn. Temperatures near 25°F may result in mortality depending on duration of low temperatures. Semi-hardy ferns grow best where nighttime temperatures are mostly above 40°F and can survive short periods of freezing temperatures if not too severe. Semi-hardy ferns are good choices for inland valleys along warmer coastal regions.