Phormium tenax

15 Aug

Phormium tenax (24/07/2011, Barbican London)

Position: Full sun to partial shade

Soil: Well drained soil

Flowering period: Summer

Eventual Height: 3m

Eventual Spread: 2m

Hardiness: 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a

Family: Xanthorrhoeaceae

Phormium tenax is an evergreen perennial with an upright habit. Its foliage is erect, stiff, sword shaped and dark grey-green with a central groove that runs the length of the leaf. In summer it bears panicles of tubular, hermaphroditic, dull red flowers.These are followed by curved, occasionally twisted, dark, almost black seed pods which ripen from green.

Phormium tenax seed pod (24/07/2011, Barbican, London)

Phormium tenax, commonly known as New Zealand Flax, is native to the island of New Zealand. Traditionally this species was used to make most forms of Maori clothing.

Phormium is derived from the Greek phormos meaning ‘basket’, with tenax being Latin, meaning ‘persistent’ or ‘obstinate’.

Phormium tenax may be useful to the landscape architect as an evergreen perennial in maritime locations. It is tolerant of periodical flooding, even with saline water; this makes it particularly suitable for placing beside roads that receive regular de-icing during our changeable temperate winters.

The Royal Horticultural Society gave the species Phormium tenax, the Purpureum Group and the cultivar ‘Variegatum’ their prestigious Award of Garden Merit in 1993.

Phormium tenax Leaf (12/09/2015, Walworth, London)

Phormium tenax will tolerate almost any soil conditions; it will be happy at neutral, alkaline or acid pH levels, in loam or sand based soils, facing any sheltered or exposed aspect.

Ecologically, Phormium tenax will attract many species of pollinating insects such as honey bees and butterflies.

Phormium tenax requires little to no maintenance. Dead or damaged material may be removed in spring. Large clumps may be lifted and divided in spring.