T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Phormium cookianum subsp hookeri (Coastal Flax)

Kingdom: Plantae
Clade: Angiosperms
Clade: Monocots
Order: Asparagales
Family: Xanthorrhoeaceae
Subfamily: Hemerocallidoideae
Genus: Phormium
Species: P. cookianum  There are two subspecies.
Binomial name: Phormium cookianum subsp. hookeri
Common name: Wharariki, Coastal flax.

 Phormium cookianum has two sub-species that are currently recognised. The more widespread of these, Phormium cookianum subsp. hookeri This is the form that is most likely to be growing on coastal areas and is the form usually seen in cultivation.
The other subspecies, Phormium cookianum ssp. cookianum is restricted to the subalpine areas, mostly in the South Island.

Phormium cookianum subsp. hookeri is an endemic NZ flax species which is smaller (H 1m x W 1m) than the common New Zealand flax Phormium tenax. It is distinguished especially by its yellow flowers and twisted seed heads.
The leaves are less than 2 metres in length while those of P. tenax range from 1 to 3 metres in length.
The scapes (leafless flowering stems that rise from the ground) are much shorter than that of P. tenax, rising up to 2 metres in height while that of P. tenax is around 5 metres in height.
The colour of the inner tepals (outer part of a flower) is green while the outer tepals are yellow to red. In contrast the tepals of P. tenax which are a dull red, with the tips of the inner tepals being less strongly recurved. The seed capsules of P. cookianum, unlike those of P. tenax are twisted and pendulous, and may be twice as long (up to 20 cm in length).
The seed capsules of the Phormium cookianum subsp. hookeri are drooping and twisted and not erect and angled as in P. tenax.The flowers are a source of nectar for the native birds, especially the tui and the bellbird.
Most of the flax cultivars are derived from Phormium cookianum.

Phormium cookianum subsp. hookeri  growing on the Te Henui Walkway

Tui feeding


The pollen-bearing anthers on long their long filaments

The twisted seed capsules of the Phormium cookianum which hang downwards.

Top side of a leaf