Rough tree fern
Alsophila australis · Cyatheaceae
The gardener's calendar
Ideal time to plant rough tree fern: set it out when the soil is neither frozen nor waterlogged, and water generously as it establishes.
ID card
- Common name
- Australian tree fern
- Foliage
- Evergreen, semi-evergreen depending on climate
- Adult size
- 4 to 8 m in height
- Growth
- Slow to moderate
- Hardiness
- Moderate (−5 to −8 °C depending on specimens)
- Origin
- Australia, temperate coastal regions
- Soil type
- Rich, well-draining, slightly acidic
- Exposure
- Partial shade to dappled light
Care
Light Exposure
Place Alsophila australis in partial shade or dappled light, protected from direct scorching sun rays. This tree fern appreciates bright but filtered conditions, which replicate its natural forest habitat. Avoid areas exposed to dry wind or intense cold.
Watering
Keep the substrate regularly moist, without waterlogged soil. Water generously during the growing season (spring-summer) and reduce watering in winter. Mist the foliage regularly to maintain ambient humidity, which this exotic fern particularly appreciates.
Soil and substrate
Prepare a mixture rich in organic matter: potting soil, peat or coconut fiber with pine bark. Drainage must be good to prevent rhizome rot. An application of well-decomposed compost in spring promotes good growth.
Fertilizer
Apply diluted fertilizer rich in nitrogen and micronutrients every 3 to 4 weeks during the growing period. Prefer a specialized fern fertilizer or light organic feeding. Stop applications in autumn-winter.
Pruning and maintenance
Remove dead or damaged fronds at the base. Avoid drastic pruning: tree ferns regenerate slowly. Regularly clean the trunk and remove debris to prevent disease.
Diseases and pests
Watch for mealybugs, spider mites and thrips in indoor cultivation. Excess stagnant moisture can promote root rot. Inspect foliage regularly and quickly isolate any suspect plants to prevent spread.
Did you know?
Alsophila australis is one of the oldest living plant forms: tree ferns have existed for over 300 million years, long before flowering trees appeared. Its characteristic fibrous trunk is not real wood, but a dense interweaving of aerial roots, giving it surprising lightness despite its impressive size.
Where to buy it
Plant in spring or early autumn, avoiding spells of intense heat. Pick a plant with healthy foliage and roots that are not exposed. Best time: March, April, May, September.
Add this plant to my garden →Plants from the same family
- Sphaeropteris tomentosissimaSphaeropteris tomentosissima
- Soft tree fernAlsophila smithii
- Cyathea planadaeCyathea planadae
- Alsophila dealbataAlsophila dealbata
- Pedunculate oakQuercus robur
- CamelliaCamellia japonica
Tips generated and checked by Viridia — adapt them to your local climate.