New zealand flax is an evergreen plant that produces red, erect flowers. Although the plant is primarily grown for its attractive flowers, it will not produce them if planted in small containers. The plant thrives in natural conditions and prefers well-draining soil and full sun.
I. Appearance and Characteristics
Phormium tenax (called flax in New Zealand English; harakeke in Māori; New Zealand flax outside New Zealand; and New Zealand hemp in historical nautical contexts) is an evergreen perennial plant native to New Zealand and Norfolk Island that is an important fibre plant and a popular ornamental plant. The plant grows as a clump of long, straplike leaves, up to two metres long, from which arises a much taller flowering shoot, with dramatic yellow or red flowers.
The jumping spider Trite planiceps lives predominantly in the rolled-up leaves of this species. Phormium tenax is a coastal cover plant associated with significant habitat such as the breeding habitat for the endangered yellow-eyed penguin.
II. How to Grow and Care
Sunlight
New Zealand flax prefers a full sun location but will tolerate partial shade. Because it is usually grown for its foliage, full sun is not crucial. In fact, in hotter climates, hybrids might do better with afternoon shade to enhance leaf color.
Temperature and Humidity
New Zealand flax is dependably hardy and evergreen in USDA cold hardiness zones 9 to 11, but gardeners in zones 7 and 8 might find that the plants regrow each spring after dying back if they are heavily mulched and protected for the winter. More often, cold-weather gardeners grow them as potted plants that are moved to an indoor shelter for the winter.
Watering
New Zealand flax has average water needs. When planted in the garden, about one inch of water per week in the form of rainfall and/or irrigation is ideal. Potted plants should be kept consistently moist, but not soggy.
Soil
New Zealand flax is not fussy about soil; it will do well even in poor soil, provided it is well-drained. It prefers slightly acidic soil but is perfectly happy in neutral soil. When grown in containers, rich potting mix is preferred over standard potting mix.
Fertilizing
These plants tolerate poor soil and thus don’t usually require much in the way of feeding. An annual top-dressing of well-rotted compost can help provide nutrients and retain soil moisture.
Pruning
The best time to prune New England flax is in the fall. Start by removing dead, dying, or diseased leaves. Cut them off at the base. Trim again in the spring if winter temperatures have killed or damaged any leaves. If it appears the entire plant has been destroyed by a cold snap, this might not be the case. Cut the plant down to the ground and give it some time; the roots might still be perfectly healthy.
Propagation
When grown in a garden setting, clumps of New Zealand flax can get quite large and overcrowded over time. Dividing them not only gives you a new plant for your own yard or to give away, it also tidies up an old plant. Here’s how to do it:
- In the spring, lift the entire plant out of the ground with a shovel. If it is too big to move it in one piece, do it in sections.
- Shake off any excess soil, which helps to separate the clump into smaller sections.
- Cut down the leaves to about six inches with pruners or shears. This prevents the plants from toppling over when you replant them.
- You can either replant each section in a new location right away, or start new plants by potting smaller pieces each in their own container with fresh potting mix, and allowing them to grow for a month or two before transplanting them into the garden.
- Keep the newly planted New Zealand flax well-watered until you see new growth.
How to Grow from Seed
New Zealand flax can also be started from seed, although it needs a warm temperature of over 60 degrees Fahrenheit to germinate. Sow the seeds in warm soil and water them well, then wait for the seedlings to arrive. When they do, thin them out to provide plenty of room to grow.
Potting and Repotting
Phormium tenax can easily be grown in containers. Choose a rich, organic mix over traditional potting soil and keep the plant well-watered in summer’s heat, but don’t allow the plant to sit in wet soil for a prolonged period. Don’t allow the plants to experience frost. When wintered indoors, this plant prefers cool temperatures and lots of sunlight.
Overwintering
In its cold hardiness zones, overwintering is not an issue. Gardeners in zones 7 through 9 might find that their plants will die back with colder temperatures. Cover the bed with a heavy layer of mulch to protect the plant until it springs back in the warmer temps.
Pests and Diseases
Mealybugs can infest plants and are hard to eradicate from inside the long leaves. Many times it’s easiest to just dispose of the infested plant. Fungal leaf spots may also mar the leaves.
When grown indoors, these plants are susceptible to many of the common pests affecting other houseplants, including mites and whiteflies. Horticultural soaps and oils are the first options for treating these pests.
III. Types of New England Flax
New varieties of Phormium are introduced just about every year and are becoming more and more ornamental. Take a look around your local nursery to see what they’ve introduced this year. Be aware that the cultivars and hybrids are sometimes more temperamental than the pure P. tenax species plant. Established favorites include:
- Phormium tenax ‘Bronze Baby’ has bronze foliage and grows to about two feet tall with a two- to three-foot spread. It is a good choice for containers.
- Phormium ‘Duet’ is a compact plant (about one foot tall). It has green leaves edged in cream, with very stiff leaf blades.
- Phormium ‘Jester’ has bronze leaves with green striping. It is about three feet tall.
- Phormium ‘Sundowner’ has green leaves with rosy-pink margins. It is about six feet tall and wide.
IV. Uses and Benefits
- Ornamental uses
New zealand flax can grow very tall and wide, lending vertical and architectural interest to a garden. It comes in different colors, which look excellent planted mixed in with one another. Mediterranean gardens, coastal gardens, and large borders and beds are all good settings for this decorative grass. Pair it with geraniums and coreopsis for a dramatic contrast in foliage.
- Māori traditional uses
New Zealand flax was one of the most commonly used fibres for weaving prior to European contact in New Zealand, due to its wide availability and long strands. Harakeke can be woven raw to create open-weave items (where the para or the waterproof epidermis of the plant is kept intact), or processed so only the muka remains, for close-weave objects. The broad length of harakeke leaves allow weavers to create a variety of strip lengths, making the plant suitable for a range of objects and sizes.
In pre-European society, Māori had specific plantations of flax, which was their most important textile. It was prepared by cutting the green leaves close to the base before the leaves were split and woven. Various preparations of the leaves allowed the material to be used both as a hardy flat thick-woven material (as in kete and mats) and also as a fibrous twine, used for creating both rope and finely woven cloaks.
Harakeke can be boiled with hot stones to bleach strips, however dying the fibre is difficult due to the water resistant para. However, harakeke can by dyed using paru, or an iron-rich mud. Harakeke can be made more flexible with less shrinkage using the hapine technique, where a knife or shell is run across the fibre to remove moisture without breaking the surface layers.
