Not to be semantically confused with : any Toadflaxes such as Purple Toadflax (Linaria purpurea), Ivy-leaved Toadflax (Cymbalaria muralis), Sand Toadflax (Linaria arenaria), Malling Toadflax (Chaenorhinum origanifolium), Bastard Toadflax (Thesium humifusum) Flax Dodder (Cuscuta epilinum), Flaxfield Rye-grass (Lolium remotum), Toadflax-leaved St John's-wort (Hypericum linariifolium) [plants with similar names belonging to differing families]

Many similarities to : Montbretia (Crocosmia × crocosmiflora), Pott's Montbretia (Crocosmia pottsii) or Giant Montbretia (Crocosmia masoniorum) which both have long linear leaves with flowers emerging from a single curving stalk, but have smaller orange or red flowers. Also similar are Wild Gladiolus (Gladiolus illyricus) and Eastern Gladiolus (Gladiolus communis), but these have purple flowers.

Some similarities to : Yucca and to both (Common) Red-hot-Poker (Kniphofia uvaria) and Greater Red-Hot-Poker (Kniphofia × praecox) in the long sharp sword-shaped leaves (but not in any way the flowers).

Uniquely identifiable characteristics

Distinguishing Feature :

Similar species : Lesser New-Zealand Flax (Phormium cookianum) which only grows to 2m high (as opposed to 3m high for New-Zealand Flax) and with leaves up to 2m high and 7cm wide (as opposed to 3m and 7cm wide for New-Zealand Flax) with flowers somewhat thinner in proportion and looking more like miniature quarter-peeled bananas - the flowers are slightly shorter flowers at 2.5cm - 4cm (as opposed to 3-5cm) but the inner petal lobes are strongly recurved (only weakly or not at all recurved in New-Zealand Flax).

No relation to : Toadflaxes such as Common Toadflax, nor to Perennial Flax, Fairy Flax or Cultivated Flax, nor to New-Zealand Pigmyweed nor New-Zealand Willowherb, nor to New-Zealand Holly or New-Zealand Bitter-cress [plants with similar names belonging to differing families].

It has six 'petals' (actually tepals): three inner and three outer.

Apart from the Scilly Islands it has hardly any natural presence in the UK, and almost all found elsewhere, such as this specimen, would have been planted, usually near the sea where it is used as an architectural ornamental plant. The above specimen is probably a cultivated variety which is not quite the same as that which grows naturally in New Zealand. It has a somewhat brutal appearance, especially when in seed.

A smaller version, Lesser New-Zealand Flax (Phormium cookianum) has also been spotted naturalising in the UK in the past in one place. Both grow naturally in New Zealand and were used by the Māori for the fibre in the leaves.

In New Zealand it is found growing alongside river banks and in swamps or low-lying areas. In the scientific name Phormium tenax, Phormium means 'basket' whilst tenax means 'tenacity', a name used by a glue manufacturer in the 1960's referring to its tenacious capacity to hold fast.

The fibres in the leaves are used to make wickerwork, baskets and perhaps rope, just as Cultivated Flax is, but that is not related to New-Zealand Flax. It has recently been found that New-Zealand Flax is closely related to Day-Lillys (in the Hemerocallis genus, which is in the same Asphodel Family (Xanthorrhoeaceae) that New-Zealand Flax resides in).

It contains poisonous Cucurbaticins and their glycosides the Arvenins such as Arvenin I which are more associated with plants of the Marrow family (Cucurbaticaeae) of which White Bryony is but one.