How to choose a Phormium plant?

Choosing a Phormium based on the colour of its leaves.

Foliage is Phormiums’ principal ornamental asset, giving them exotic appeal and lushness. It consists of long, linear, sword-shaped or ribbon-like leaves that extend towards the sky or cascade down as a genuine cascade of foliage. They form a dense, leathery tuft in a fan shape.

The genus Phormium comprises only two species, but has given rise to numerous cultivars prized for their foliage colours. From varieties with variegated, striped, bright or, on the other hand, very dark foliage, from the most classic to the most astonishing, you will surely find a Phormium to suit your tastes.

Foliage in green tones

Among Phormiums, cultivars never truly settle for conventional green leaves, except in the standard species such as the Phormium tenax. Many indeed rely on variegation, particularly with yellow. This makes it easy for them to bring light and sparkle, for example within a border.

‘Golden Ray’ has leaves of a bright green, variegated with yellow along their entire length and bearing a fine orange-red margin. The tall ‘Variegatum’ opts for a yellow-cream variegation, as does ‘Cream Delight’.

In ‘Yellow Wave’, the dominant colour is yellow, as its name suggests. The leaves are lime-green variegated and traversed by mid-green stripes.

Even warmer, the leaves of ‘Apricot Queen’ offer different shades of yellow and green, with a contrasting red margin. The colour then evolves to olive-green to bronze tones, striped with yellow and apricot-orange.

More original, ‘Chocomint’ pairs chocolate brown with mint green, while ‘Sundowner’ offers bronze-green edged with pink or salmon, with nuances varying with the season.

Foliage in pink tones

Here, our New Zealand flaxes embrace originality with foliage colours that are rarely seen, further emphasising the exotic character of these perennials.

Let’s begin with the extravagant ‘Jester’: its leaves blend a vivid pink, pink tinged with bronze and margined with pale green. In the same vein, ‘Pink Panther’ treats us to pink leaves margined with bronze, brown and ruby red.

‘Evening Glow’ offers, for its part, pink margined with purple.

Among varieties blending pink, bronze, olive green and red, we should also mention ‘Margaret Jones’, ‘Rainbow Queen’, ‘Pink Stripe’, ‘Rainbow Sunrise’ and ‘Flamingo’.

Foliage in very dark tones

Phormiums are among those plants that can display foliage so dark it almost looks black, depending on light and sun reflections. These are varieties with a lot of character, able, for example, to serve as a chic, contemporary focal point in a large container or as a specimen in the garden.

This is the case with the Phormium cookianum ‘Black Adder’, with leaves purplish to dark burgundy.

A somewhat lighter option is the Phormium tenax ‘Purpureum’ which offers purple leaves shaded with bronze. In its turn, ‘Dark Delight’ opts for leaves with chocolate to dark purple hues depending on light, as does ‘Platts Black’.

‘Black Velvet’ produces leaves of purplish-black with metallic reflections, very glossy and satin on the reverse.

Finally, let us mention ‘Special Red’ with leaves in warm and dark tones, red-brown shaded with bronze.

On the left Phormium ‘Sundowner’, on the right ‘Jester’ and ‘Black Adder’.

Choosing a Phormium based on its flowering.

The flowering of Phormiums occurs only in certain varieties. It is a fairly rare and rather sparse phenomenon that can only occur after several years of cultivation.

Flowers appear between May and July, depending on the mildness of the climate. The Phormium then produces long flowering stems, at the top of which small tubular flowers reveal themselves, grouped into upright panicles. After flowering, the rosette dies back, but it will have produced an offset to ensure its longevity. After this flowering, small fruits appear in a spiral form. They are trailing in Phormium cookianum, more erect in Phormium tenax.

Among ornamental-flowering varieties you may be lucky enough to observe, notable examples include ‘Golden Ray’ with vivid red flower spikes, ‘Variegatum’, ‘Evening Glow’ or also ‘Apricot Queen’.

On ‘Black Adder’, the flowers are green, with touches of yellow and orange. On ‘Yellow Wave’, a green tinged with purple is chosen.

A Phormium tenax in flower.

Choosing a Phormium according to its silhouette and its use

In its natural habitat, Phormium can exceed 3 metres in height, but it will be less expansive in our metropolitan gardens. The smaller ones will not exceed 30 cm in height, while the largest will reach around 2.50 metres.

Small varieties

They are ideal for pot culture, borders, rockeries that aren’t too dry, or as the foreground in a border. You can plant them in groups for a richer, more luxuriant effect. These are compact specimens that form adorable mini‑tufts of vegetation, not exceeding 80 cm in height.

This includes ‘Cream Delight’, compact and regular with 75 cm across, or again ‘Special Red’, which does not exceed 50 cm across. The Phormium cookianum ‘Blondie’ measures 60 cm tall and as wide. It stands out thanks to its linear, slender, slightly twisted foliage.

Generally, varieties derived from Phormium cookianum (or P.colensoi) are smaller, not exceeding 1.60 metres tall. In terms of silhouette, the foliage will be less broad and less erect, hence more fountain-like in habit.

The most imposing varieties

These Phormiums measure between 2 metres and 2.50 metres in height. They will form an opulent and generous clump of plants, adding substantial volume to the garden. Plant them as standalone specimens, or in a large border or a large rock garden.

This includes ‘Variegatum’ or also ‘Purpureum’. The type species P. tenax is also the most vigorous, capable of exceeding 2.50 metres if cultivation conditions are favourable.

The small ‘Blondie’ does not exceed 60 cm, but Phormium tenax reaches at least 2.50 m in all directions.

Choosing a Phormium according to growing conditions

Hot and dry climates

The Phormium tenax is the most cultivated in gardens. It is the species that tolerates Mediterranean drought and heat conditions best. Its cultivars will carry these traits.

The moister climates

The P. cookianum, also known as ‘Phormium des montagnes’, will prefer moister climates, notably on the Atlantic coast. The varieties derived from it will also prefer these mild and well-watered conditions, such as ‘Tricolor’ or ‘Black Adder’.