Royal Mail

All Tools, Selected Irrigation & Lifestyle Acessories

Delivery By Us

All Plants, Niwaki Ladders, Pots & Selected Irrigation

Collect From Our Nursery

Anything From Our Online Shop ~ We'll Help You Load It

Consult Our Team

Unsure About Your Order? We Can Help

Phormium tenax ‘Purpureum’ (New Zealand Flax)

Glaucous, erect and spiky are the hallmarks of the New Zealand Flax (Phormium tenax). Green, soft, floppy and luxuriant are the hallmarks of the less well known Mountain Flax (Phormium cookianum). This can grow to 6ft x 4ft wide with flower spikes to 10ft and is pure drama and as the name suggests, the leaves are purple. It’s less hardy than the other Phormiums but being a New Zealander, it starts growing at quite low temperatures so frost damaged plants are best cut down to nothing by the end of Feb and will start re-growing in March.

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. We find the broad leafed forms of Phormium less hardy than the narrow leafed and more erect forms. A well grown one of these is an explosion. They remind me of my drawings of tanks blowing up. I haven’t done a drawing of a tank blowing up for quite a while but I suspect that were I to be called upon to do one now, it would still look like a particularly fine example of a New Zealand Flax. We call them Phormium tenax. Kiwis call them Flax Bushes; usually in a slightly bored sounding voice. I know there are an awful lot of Flax Bushes in New Zealand but we still get quite excited by them back in Blighty.

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. Could you make pink food dye from squished mealy bugs. Probably but might not bother.

Severe frost (-4°c or below) will give the leaves a glazed look and the leaves tend to roll up. It can look terminal but it’s not. They recover wonderfully well as soon as the temperature rises.

Propagated by division.

One last thing : the leaves of Phormium tenax produce the strongest known natural fibre known. Get one caught round the blades of your ride on mower – even if it is a twin cylinder 16 H.P. diesel – and it’ll stop it dead. There is some confusion as both Linen Flax (Linum usitatissimum – known as Flax) and New Zealand Flax (Phormium tenax – known as Flax) are used for making rope. Thank God for Latin names.

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.