This large tree-fern has a blackish trunk that is covered in oval leaf scars and becomes thick at the base. It has large dark green leathery textured fronds that are twice divided and the spored are produced on the fertile fronds during spring.  

Hardiness zones 9 to 11 

Cyathea brownii is naturally found on Norfolk Island growing in sub-tropical rainforest on the coast and into the lower mountains. It prefers an organic rich moist soil that is tending acidic and grows in a semi shaded to sunny wind protected position with high humidity and is frost and drought tender. 

The Norfolk Island Tree-fern is grown for its spreading fronds and is planted in tropical gardens as a specimen or in groups along water courses or as an understorey amongst trees. It is suitable for coastal and low mountain regions establishing in 2 to 3 years. It is also used as a container plant when young and may be planted in courtyards or around the shaded side of buildings. ID 2888

Note:
This is the largest tree-fern species and requires ample space to grow and must have reliable moisture. 

Cyathea (sy-AY-thee-ah) brownii (brown-ee-eye)

Cyatheaceae (sy-AY-thee-AY-see-ee)