Phormium cookianum ‘Tricolor’ (Mountain Flax)

Green, soft, floppy and luxuriant are the hallmarks of Mountain Flax (Phormium cookianum) – as opposed to glaucous, erect and spiky being the hallmarks of the better known New Zealand Flax (Phormium tenax). Also, they are smaller and although the flower spike is much the same, the flowers are yellow rather than deep red. Some might consider this to be more tasteful, more accommodating. Always nice to have a plant named after the great Captain Cook. The name Tricolor refers to the green of the leaf, the white of the striped variegation and the red of the stripe down the sides of the leaves. This plant can grow to 4ft x 4ft with 6ft flower spikes.

All Phormiums (whether P. tenax or P. cookianum) are described by proper botanists as having a ‘broad genetic base‘. This means highly variable and incredibly unpredictable. Sow 1000 seeds and hardly any will be the same; they will vary in the way they look and their frost hardiness. This plant is remarkably frost hardy and is propagated by division – so they’re all the same plant.

Phormiums don’t like shade and they’re very good in the wind so exposed spots are good. Creative Maintenance on these is time consuming but worthwhile. Remove old leaves and flower spikes with sharp secateurs or a sharp knife. Sometimes the leaves on this plant can be pulled off using two hands and a good sharp tug. Look out for Mealy Bug as you go. They’re an aphid that looks like a tiny white Wood Louse that loves living in the bases of all Phormiums. They produce copious quantities of white fluffy stuff which is always a dead giveaway. The plants will tolerate their presence but best to kill them if you can. Religious use of a bug gun should do the trick. Stick them with your marlin spike and they’re red inside – blood? They’re related to the Cochineal beetle (they’re both considered Scale Insects) which is crushed to make the red food dye – cochineal. Yuck, you may well say.

Propagated by division by us. Can grow to 5ft x 5ft in ideal conditions (rich, well drained soil and plenty of light)

Hardiness traffic light amber

Hardiness level Amber

Find out more

Hardy in the Home Counties if sensibly sited (avoiding severe frost pockets, for example). Many Amber Labelled Plants are from cuttings from well-established plants that have survived many harsh winters in the South-East.

This is only meant as a guide. Please remember we're always on hand to give advice about plants and their frost hardiness.

Please remember that these coloured labels are only a rough guide.

General Point about Plant Hardiness: The commonly held belief that it's better to 'plant small' is perfectly true with herbaceous plants, but not necessarily true with woody plants. They need some 'wood' on them to survive severe cold - so plants of marginal hardiness in very cold areas should really be planted LARGER, rather than smaller, wherever possible.

Contact us for availabilityBook a Visit