Phormium tenax

Position and soil. North Carolina State Extension and the Missouri Botanical Garden give full sun to part shade in average, well-drained soil, and Missouri says it tolerates a wide range of soils, poor ones included, and considerable shade; the variegated forms colour best in part shade by North Carolina State Extension and in filtered sun by Missouri. An archived Victorian weed profile quotes a garden reference rating its drought tolerance medium and its salt wind tolerance high, and North Carolina State Extension calls it highly salt tolerant.

Frost. The same Victorian profile quotes one reference calling it fairly frost hardy and another as giving at least -5 C. The American references call it tender and rate it on their zone system only. No Australian reference read gives climate zones.

Pests. American references name mealybugs, snails or slugs and leaf spot. A New Zealand reference quoted in the Victorian profile names a soft white scale insect and the leaf-cutting flax moth as its two serious pests.

Propagation. By seed or by division in spring, by the reference quoted in the Victorian profile; the New Zealand Plant Conservation Network says it is very easy from fresh seed and most commonly grown by dividing rooted fans.

Growers list this plant under Phormium tenax and under the genus alone, and the New Zealand Plant Conservation Network says most cultivated material is a mixture of hybrid, variegated and colour mutations, the wild forms now rarely sold. Phormium tenax has naturalised in Australia: the Australian Plant Census records it naturalised in Western Australia and Tasmania and doubtfully so in South Australia and New South Wales, PlantNET records it naturalised near Katoomba and Lawson, HortFlora says it is naturalised in parts of Victoria, and the Weeds of Australia fact sheet says it is possibly naturalised in southern Victoria and regards it as an environmental weed in Tasmania and Victoria. What to check in the pot is in the guide to nursery plant quality. Stock that crosses a state border moves under the state and territory biosecurity rules on moving plants and soil.