The world's fastest-growing tree fern with a black hexagonal-patterned trunk, up to 20 meters tall

Sphaeropteris medullaris, the black tree fern, is one of the most impressive tree ferns in the world. It can reach a height of up to 20 meters with a trunk up to 20 centimeters in diameter, making it the tallest tree fern in New Zealand. The species is widespread in the Southwest Pacific from Fiji to Pitcairn Island and is a common plant in New Zealand's forests.

The trunk is black and covered with characteristic hexagonal leaf scars that create a striking geometric pattern. The fronds can grow up to 6 meters long and arch upwards from the crown in an elegant curve. Sphaeropteris medullaris is one of the fastest-growing tree ferns, able to grow up to 50 centimeters per year. It is a pioneer plant that colonizes disturbed slopes in many high-altitude moist forests.

Care

In areas prone to frost, it is grown in pots under glass with a minimum winter temperature of 10 degrees Celsius. The plant can be placed outdoors during the summer in a sheltered and semi-shaded spot.

It requires moist but well-drained, humus-rich soil. During hot, dry summers, both the trunk and the soil should be watered, but avoid watering the crown in winter. Fertilize with liquid fertilizer monthly during the growing season.