Fern Tree

The Fern Tree (Cyathea cooperi, also sold as Sphaeropteris cooperi) is the fastest growing of the Australian tree ferns, and the quickest way to put a rainforest canopy over a shaded courtyard. It reaches about 5m tall with a frond spread near 3.5m, on a slim fibrous trunk that takes up almost no ground space. Its roots are non invasive and it is not toxic to cats or dogs.

Why you'll love it

• Speed you can actually see. Of all the tree ferns this is the one that moves. Given warmth, water and shelter it pushes a new flush of fronds through every warm month.
• A canopy without a root problem. Non invasive roots mean it can go close to paving or a pool surround where a shade tree would cause trouble.
• Safe around pets. It carries our Pet Friendly rating, which matters for a plant at ground level in a courtyard a dog uses.
• Takes damp ground. Wet feet tolerant, so the low corner that stays soggy after rain becomes an opportunity.
• Wide climate range. Grows in tropical, subtropical, warm temperate and cool temperate gardens, unusual for a plant this lush.

Where it works best

Feature planting. One mature fern changes the feel of a whole courtyard. Uplight the trunk and the silhouette does the work at night.

Fern groves and mass planting. Plant 2m apart. At that spacing the crowns overlap into a continuous green ceiling while each trunk stays visible underneath.

Poolside and small gardens. The narrow trunk and contained roots suit a tight bed beside a pool.

Growing the Fern Tree in Australia

Position and climate. Filtered light or part shade is ideal, and shelter from hot dry wind matters most, because wind desiccates the fronds far faster than sun does. It takes light frost only, so in cold inland and highland gardens choose a protected spot under a canopy and expect frond burn in a hard winter.

Soil. Rich, organic and moisture retentive. Dig in compost generously and mulch 75mm deep, clear of the trunk.

Water. Water the trunk and the crown, not just the soil. The trunk is a mass of aerial roots that absorbs moisture directly, so a daily hose over it in hot weather is the difference between lush fronds and crisp brown ones.

Feeding and grooming. Slow release fertiliser in spring, plus the occasional bucket of weak liquid feed poured into the crown. Cut old fronds off close to the trunk once they brown, wearing gloves.

What to expect when it arrives

Fern Trees are grown in sizes from 140mm and 200mm packs through 250mm, 300mm and 400mm pots up to 45L, 100L and 200L. The smaller pots arrive as a crown of fronds with no visible trunk yet, and they are the value choice for a grove if you can wait: the trunk lifts within two to three years in a warm garden. Large containers arrive already trunking.

Plants are packed upright with the fronds protected and delivered Australia wide, with delivery from $29.95. Advanced and large stock is freighted at cost. Some frond damage in transit is normal, because the plant replaces its canopy within a season. Every plant carries our 30 day healthy plant guarantee.

Plant care guides and related reading

• Browse ferns for shady areas
• More Australian natives for habitat gardens
• Build the rest of the tropical planting
• Preparing a garden bed before planting

Common questions

How much sun can it take?

Filtered light suits it best. It handles more sun in a humid coastal garden where the air stays moist, but in a dry inland garden afternoon sun scorches the fronds however much you water.

Why are the fronds going brown at the tips?

Usually dry wind or a dry trunk rather than a soil problem. Hose the trunk and crown in hot weather, add a windbreak, and trim the spent fronds off. The crown replaces them.

Is it safe around dogs and cats?

Yes, it carries the Pet Friendly rating. Note that the fine scales on the trunk and unfurling fronds can irritate human skin, so wear gloves when you groom it.