Cyathea brownii - S

About the Cyathea brownii - S

Cyathea brownii, also known as Sphaeropteris excelsa, is an evergreen tree fern from Norfolk Island. The plant develops a single trunk topped by a broad crown of large, gracefully arching and finely divided green fronds. In mature specimens, the trunk may become relatively smooth and display oval leaf scars. In size S, this species can be grown in a container, although its mature dimensions will eventually require considerably more space. The commercial size S alone gives no indication of the age or developmental stage of the specimen offered.

Characteristics

Origin: This species is native exclusively to Norfolk Island, where it grows in moist forests.

Family: Cyatheaceae, a family of tree ferns.

Position: A warm, sheltered position away from drying winds. For container cultivation, a greenhouse, conservatory or spacious indoor environment is suitable when sufficient warmth, light and humidity can be provided. During frost-free periods, the plant can be placed outdoors in a sheltered position.

Height: In the wild, this tree fern commonly reaches approximately 5 metres in height, while exceptional specimens can reach around 18 metres. The fronds of mature plants can grow to approximately 5 metres long. Growth remains considerably more restricted in a container.

Flowering period: Not applicable. Tree ferns do not flower but reproduce by means of spores.

Flower colour: Not applicable, because this species does not produce flowers.

Hardiness: Not winter hardy. Protect the plant from frost and prolonged cold and overwinter it in frost-free conditions in the Netherlands.

Soil type: A humus-rich, airy and well-drained substrate that retains sufficient moisture without remaining wet for prolonged periods.

Care

Light: Provide plenty of bright, filtered light or light partial shade. Protect the fronds from harsh midday sun and acclimatise the plant gradually to direct sunlight.

Water: Keep the substrate evenly moist and do not allow the root ball to dry out completely. Water generously when the surface begins to dry, but allow excess water to drain away fully and prevent standing water around the roots.

Fertiliser: During active growth, regularly apply a limited amount of suitable fern fertiliser. Reduce feeding when growth slows and avoid overfertilising.

Pruning: Remove only completely dried or damaged fronds. Cut them close to the trunk without damaging the crown or growing point.

Repotting: Repot when the roots have largely filled the available container space. Use a container that is only slightly larger, has drainage holes and is sufficiently stable for the increasingly broad crown.

Humidity: High humidity supports healthy frond development. Indoors, protect the plant from dry heated air while also providing adequate air circulation.

Special features: Cyathea brownii is among the largest tree ferns in the world. New fronds unfurl from the central growing point, so take care not to damage the crown.