How to grow lacy tree fern
Overview
Lacy tree fern is a fast-growing, evergreen fern with delicate, lacy fronds. It is grown as a striking foliage feature in sheltered, moist gardens. This fern needs consistent moisture and protection from frost to thrive.
Varieties
- Cyathea cooperi 'Brentwood' — A compact selection with denser fronds, ideal for smaller gardens.
- Cyathea cooperi 'Robusta' — A more vigorous form with thicker trunk and broader fronds.
Soil Preparation
Lacy tree fern prefers rich, acidic to neutral soil (pH 5.5–7.0) with excellent moisture retention. Amend heavy clay with compost and coarse sand to improve drainage. Avoid waterlogged sites; ensure the soil is consistently damp but not sodden.
Growing Guide
Plant lacy tree fern in a sheltered position with dappled light or morning sun, avoiding harsh afternoon rays. Space specimens 2–3 metres apart to allow for their full canopy spread. Prepare a deep, wide hole and enrich with well-rotted organic matter, ensuring the crown sits at soil level. Water thoroughly after planting and maintain consistently moist soil, especially through the first two summers. Mulch heavily with bark or compost to keep roots cool and damp.
Sowing
Lacy tree fern is rarely grown from seed in home gardens; it is typically propagated by spores or division. Spores require a sterile, humid medium and take several months to germinate. Most gardeners buy established plants from nurseries.
Care
Feed with a balanced slow-release fertiliser (e.g., 8-3-9) in spring and summer to support rapid growth. Prune away old or damaged fronds at the base using clean secateurs to keep the plant tidy. Replenish mulch annually to maintain moisture and suppress weeds.
Companion Planting
Pair lacy tree fern with other shade-loving plants like hostas, bromeliads, and cliveas for a lush tropical understorey. Avoid planting near shallow-rooted trees that compete for moisture, such as eucalypts or acacias.
Common Pests & Risks
Scale insects can infest the fronds, causing yellowing and sooty mould. Treat with horticultural oil or neem oil in early spring. Dry conditions may lead to frond tip burn; maintain high humidity and regular misting to prevent this.
Troubleshooting
Yellowing fronds: caused by overwatering or poor drainage; reduce watering and improve soil aeration. Brown frond tips: due to dry air or underwatering; increase misting and check soil moisture. Stunted growth: from nutrient deficiency; apply a balanced fertiliser in spring. Scale on fronds: treat with neem oil or horticultural oil. Frond drop: from frost damage; protect with shade cloth in cold snaps.