Phormium tenax 'Radiance' (New Zealand Flax 'Radiance') — Evergreen perennial

Overview

Phormium tenax 'Radiance' is a evergreen perennial in the genus Phormium, part of the Asphodelaceae family, with evergreen foliage. It typically grows around 3.0 m tall. Phormium tenax 'Radiance' grows best in full sun, and tolerates most soils. Its UK hardiness is rated H4. Suggested uses include borders, containers and architectural plant. It is native to New Zealand.

About the genus

Phormium is a genus of two plant species in the family Asphodelaceae. One species is endemic to New Zealand and the other is native to New Zealand and Norfolk Island. The two species are widely known in New Zealand as flax or their Māori names wharariki and harakeke respectively, and elsewhere as New Zealand flax or flax lily, but they are not closely related to the Northern Hemisphere's flax, which is native to the region extending from the eastern Mediterranean to India and has been used by humans since 30,000 B.C.

Wikipedia contributors, "Phormium", CC BY-SA 4.0 — Phormium

In the garden

Phormium tenax 'Radiance' originates from New Zealand and is cultivated for its architectural form and year-round foliage. In UK gardens it performs best in a full-sun situation and will tolerate a range of soils — sandy, loamy or clay — provided they remain moist; it also copes with wetter spots. Exposure should be full sun to match the plant's preference. Hardiness is H4, which means it is suitable for most average UK gardens; in regions that are colder or exposed you should site it where it gains warmth from the sun and some shelter from harsh winds. It is also classed for USDA zones 8–10, useful information for gardeners outside the UK. Allow space for its height — the plant reaches about 3.0 m — and consider a large container if ground space is limited. Suggested uses include bold borders, specimen containers and architectural placements where its vertical scale can be appreciated. Expect the plant to flower from June to August; allocate position and space accordingly so the flowering stems can be seen above surrounding planting and contribute to the intended composition.

Growing conditions

Best soil and position for Phormium

Sunlight: Full sun
Soil type: Sandy, Loamy, Clay
Soil moisture: Moist but well-drained, Wet
Exposure: Full sun
UK hardiness: H4

Plant details

Phormium tenax 'Radiance' size, habit and characteristics

Plant type: Evergreen perennial
Foliage: Evergreen
Height: 3.0 m
Suggested uses: Borders, Containers, Architectural plant
Native to: New Zealand

Care notes

Pruning and caring for Phormium tenax 'Radiance'

Cultivation: Prefers moist but well-drained soil; tolerates wet conditions; plant in full sun for best leaf color
Pruning: Remove old or damaged leaves to maintain appearance
Propagation: Division of clumps in spring or autumn

Frequently asked questions

How do I grow Phormium tenax 'Radiance'?

Prefers moist but well-drained soil; tolerates wet conditions; plant in full sun for best leaf color.

Where is the best place to plant Phormium tenax 'Radiance'?

Phormium tenax 'Radiance' prefers full sun. It suits full sun positions.

What soil does Phormium tenax 'Radiance' need?

Phormium tenax 'Radiance' is adaptable and grows happily in most soil types, including sandy, loamy and clay. Aim for soil that stays moist but well-drained to wet.

How do I prune Phormium tenax 'Radiance'?

Remove old or damaged leaves to maintain appearance.

How big does Phormium tenax 'Radiance' grow?

Phormium tenax 'Radiance' reaches a height of 3.0 m.

Is Phormium tenax 'Radiance' hardy in the UK?

Phormium tenax 'Radiance' has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.