Castlewellan Gold

Castlewellan Gold (Cupressocyparis leylandii 'Castlewellan Gold') is the golden form of the fastest hedging conifer grown in Australia. Left untrimmed it reaches about 10m tall and 4m wide, but almost nobody grows it that way: trimmed twice a year it holds a dense, tall and narrow screen at whatever height you set. New growth carries a soft gold flush that deepens to bronze green in winter. Planted 1.5m apart it closes a boundary faster than any broadleaf hedge.

Why you'll love it

• Speed you can plan around. Few plants close a gap this quickly, which is why it is the default when a boundary needs covering in two seasons rather than five.
• Naturally tall and narrow. It grows up rather than out, so a 4m or 5m screen costs you only a metre of garden depth.
• Gold that lifts a green fence line. The colour is strongest on new growth in full sun, and reads as warmth rather than variegation.
• Genuinely tough. Frost hardy, wind tolerant, salt tolerant and drought tolerant once established, so exposed rural blocks and coastal fence lines both suit it.

Where it works best

Privacy screening. Plant 1.5m apart in a single row. That spacing gives each plant room to fill to the ground and closes into a continuous wall within two to three seasons.

Formal hedging. It clips well and holds a crisp face. For a hedge you intend to keep at 2m to 3m, trim the sides from the first season rather than waiting until it reaches height.

Windbreaks. A staggered double row at 1.5m to 2m gives a dense evergreen shelter belt along an exposed rural boundary.

Growing Castlewellan Gold in Australia

Position and climate. Full sun, always. In shade the gold fades to green and the base thins. This is a cool temperate, warm temperate and Mediterranean plant, fully frost hardy and reliable through southern winters. It is the wrong choice for humid tropical and subtropical gardens, where wet summer heat encourages dieback in the inner foliage.

Soil. Drainage matters more than fertility. On heavy clay, plant on a mound 200mm high and work gypsum and compost through the row. Waterlogged roots are the usual cause of a browned out hedge.

Water and feed. Deep soak twice a week for the first summer, then water in dry spells only. A slow release fertiliser in early spring is enough; too much nitrogen just means trimming every six weeks.

Pruning. Trim twice a year, after the spring flush and again in late summer. Always cut back to green foliage, because this conifer will not reshoot from bare brown wood.

What to expect when it arrives

It is grown in eight sizes. The 140mm pack of ten and 200mm pack of six are the sensible choice for a long boundary, since small plants catch large ones quickly. The 250mm pack of three and 300mm are the usual middle ground, while the 400mm, 45L, 70L and 100L arrive with real height on the plant.

Plants travel upright and are delivered Australia wide, with delivery from $29.95. Advanced and large stock is freighted at cost. Expect a quiet three or four weeks while the roots establish, then rapid growth through the first warm season. Every plant is covered by our 30 day healthy plant guarantee.

Plant care guides and related reading

• Compare Leighton Green, the plain green form
• Browse hedging and screening plants
• Preparing a garden bed before planting

Common questions

How far apart should I plant it?

One and a half metres apart in a single row. Planting tighter does not close the screen faster, and it produces thin drawn plants that go bare at the base.

Can I keep it at 3m?

Yes, and most people do. Trim the top and both sides twice a year from the year you plant, always cutting into green growth, because bare inner wood will not reshoot.

How does it differ from Leighton Green?

Colour and size. This selection has golden new growth and settles at around 10m untrimmed, while Leighton Green is plain deep green and reaches 12m.