Cordyline indivisa aka Mountain Cabbage Tree

Cordyline indivisa is a slow-growing tree that can reach up to 8 meters (26 feet) tall in its native New Zealand habitat, with a trunk diameter of 40-80 centimeters and a spread of approximately 2 meters. The distinctive blue-grey leaves are among the broadest of any Cordyline species, measuring 1-2 meters long and 10-30 centimeters wide. When grown in containers, plants typically stay much smaller at 1.2-1.8 meters (4-6 feet). The plant develops a palm-like appearance as it matures and naturally sheds its lower leaves.

Cordyline indivisa prefers cool temperatures and struggles in hot, humid weather. Native to New Zealand's misty mountain environments, it thrives in temperatures between 10-20°C (50-68°F) and can tolerate cold down to approximately -3°C to -10°C (27-14°F). The plant tends to grow more vigorously during cooler months than during summer heat. In hot conditions, it may suddenly collapse or decline. If damaged by severe frost, it can often regenerate from the base.

Cordyline indivisa produces compact, drooping flower panicles in late spring to early summer (November-January in its native Southern Hemisphere). The fragrant flowers are white, yellowish, or mauve with purple tones, appearing beneath the leaf crown. Following pollination, small bluish to dark blue globose berries (approximately 6mm diameter) develop from January to May. Indoor specimens rarely flower, and in lowland or warm climates, few plants survive long enough to reach flowering maturity.

Cordyline indivisa can be grown outdoors in USDA zones 8-10 (UK zone H4), but success depends heavily on climate conditions. It thrives in cool, moist environments similar to its native New Zealand mountain forests and does well in coastal areas with maritime influence. In hot, dry regions, outdoor cultivation is extremely difficult. The plant requires protection from strong winds and intense sun. Excellent drainage is essential, but the soil must remain consistently moist. Outstanding outdoor specimens exist at Castlewellan and Mount Stewart gardens in Northern Ireland.

Cordyline indivisa is most easily propagated from seed. Pre-soak seeds for about 10 minutes in warm water, then sow in late winter to early spring in a warm greenhouse. Germination typically takes 1-3 months at 25°C (77°F) with good success rates. Stem cuttings are also possible: cut 5cm thick blocks from the stem and place 3cm deep in pure peat in a heated frame, potting individually once rooted. Suckers can be removed in early spring. Plants dislike being moved once established, so plant in their permanent position while young.

Cordyline indivisa generally dislikes container growing and should be planted out in the ground when young if possible. If keeping in containers, repot when the plant has doubled in size, using a well-draining potting mix rich in organic matter.

Cordyline indivisa requires minimal pruning. The plant naturally sheds its lower leaves as it grows, developing a clean trunk. You can remove dead or damaged leaves by cutting them close to the trunk. If the plant has been damaged by frost, wait until new growth appears before removing any affected foliage, as the plant can regenerate from its base. Avoid heavy pruning, as this can stress the already temperamental plant.

Cordyline indivisa has no serious insect or disease problems. The main threats are environmental rather than pest-related: the plant tends to collapse during hot, dry weather or water shortage. Young plants are particularly vulnerable to damage from mice. In hot, humid conditions, root rot can occur if drainage is poor. The biggest challenge is maintaining the cool, moist conditions this temperamental species requires rather than dealing with pest infestations.

Yellow leaves on Cordyline indivisa typically indicate environmental stress. The most common causes are excessive heat, insufficient water, or poor drainage causing root problems. This species requires consistently moist (but not waterlogged) soil and cool temperatures. If the plant is experiencing hot weather or drought stress, it may yellow and decline rapidly. Check that the soil drains well while retaining moisture, and ensure the plant is protected from intense heat and direct afternoon sun.

Brown leaf tips or edges on Cordyline indivisa usually indicate insufficient humidity or water stress. This mountain-dwelling species naturally thrives in misty, high-rainfall environments. Brown leaves can also result from wind damage (the broad leaves tear easily in strong winds) or sunburn from excessive direct sun. Ensure consistent watering, protect from drying winds, and provide bright but filtered light. Lower leaves naturally brown and shed as the plant matures, which is normal.

Cordyline indivisa is endemic to New Zealand, where it grows in montane forests and subalpine shrublands. In the North Island, it occurs south of the Hunua Ranges and Coromandel Peninsula, becoming common from the Raukumara Ranges southward. In the South Island, it is widespread along northern and western regions. The species thrives in mountain gullies and valley heads with deep organic soil, cool temperatures, high rainfall, and misty conditions—typically wetter montane areas rather than lowland environments.

Cordyline indivisa has several edible parts with a PFAF edibility rating of 3 out of 5. The roots can be baked, and the trunk pith can be dried and steamed for use in porridge or sweet drinks. Young shoots can be eaten as a cabbage substitute. The root and stem are notably rich in fructose, with yields comparable to sugar beet. The small fruits (about 6mm) are also technically edible. Note that while the plant is safe for human consumption, it is toxic to cats and dogs.

Cordyline indivisa has traditional uses primarily for fiber production, rated 2 out of 5 for other uses by PFAF. The leaves yield strong fibers used historically by Māori for making paper, twine, cloth, baskets, thatching, and rain capes. The leaf midrib produces a distinctive red-colored plaiting material. Rope made from this plant is reported to be stronger and more water-resistant than some alternatives. The plant is also valued ornamentally as a striking architectural specimen.

Cordyline indivisa has hermaphroditic (bisexual) flowers that are pollinated primarily by insects attracted to their fragrant scent. The drooping flower panicles produce white to mauve blooms in late spring to early summer. After successful pollination, bluish-black fleshy berries develop, which are consumed by birds that then disperse the seeds (frugivory). Indoor specimens rarely flower, so pollination is mainly relevant for outdoor or greenhouse-grown plants.