Family: Dicksoniaceae

From tropical and subtropical regions, includ­ing Australia, New Zealand and the South Pacific, this genus of evergreen to semi-ever­green tree ferns comprises around 25 species. The trunks can be either large or small, the large, spreading fronds are finely divided, and the hairy stems thicken towards the base. The spore cases on fertile fronds are protected by a pouch-shaped cup which breaks when ripe and releases the spores. These tree ferns make fine specimen plants, but if space permits, group­ings of several create a much better effect.

Species

D. antarctica, soft tree fern, zone 8, is distributed throughout mountainous areas of eastern Australia and New Zealand. Hardy and adaptable, it is a popular garden species, need­ing some overhead protection. It has a solid trunk which can grow to 10 m (33 ft) high, a profusion of large, spreading fronds, providing a beautiful display, and sterns which are cov­ered in masses of reddish brown hairs.

D. fibrosa, wheki-punga, zone 9, is a native of New Zealand. Its trunk grows to about 7 m (23 ft) tall and is a reddish brown colour because of the masses of aerial rootlets. The dark green fronds grow profusely, and the stalks are cov­ered with brown hairs when young, darkening with age.

D. squarrosa, wheki, zone 9, also from New Zealand, has a black, slender, often branched trunk as young plants form at inter­vals up the trunk. The masses of glossy, green fronds, which are lighter on the undersides, form a rather flat top, unique to this handsome tree fern.

Cultivation

Grow in acid soil in partial or full shade. Give plenty of water to the base and trunk and a fine spray over the crown to keep the foliage healthy. Rotted leaf mould and aged cow manure are good soil conditioners. Propagate from spores. If transplanting these tree ferns, lift as much of the root structure as possible to avoid retarding growth, or cut off the trunk, making sure that the trunk is planted about 30 cm (12 in) deep in the new position. All of the fronds, except those at the central growing point, need to be removed if the trunk is severed from its roots. They should be moved only in summer during the growth period.

Climate

Wide moisture and temperature range, depending on the species grown.