Cushion Bush Leucophyta brownii (Calocephalus brownii)

Cushion bush builds a dense, rounded tangle of fine white stems, the leaves reduced to tiny scales pressed flat against the wood so the whole plant reads as silver rather than green. Small pale button flowerheads sit on top through the warmer months and add little to a plant already working with colour and form. It comes from southern Australian sea cliffs and dunes, including coastal Victoria, South Australia and Tasmania, and it is planted as a silver accent in coastal beds, pots and against dark foliage or grey stone.

Full sun, sand and the humidity problem

Full sun is the requirement, and the harsher the position the better this plant looks: salt wind, sand, exposed corners and thin soil all suit it. What it will not take is comfort. Rich soil, a still humid pocket, heavy mulch heaped against the crown and ground that stays damp all produce the same result, which is blackening at the base and the sudden collapse of one side of the plant. That is the failure mode, and it is not a slow decline; a plant can look healthy and be dead inside a fortnight. Plant it high, on a mound or in a raised bed if your soil is heavy, and use a thin gravel or coarse sand mulch rather than bark against the stems. In humid summer districts along the east coast, plenty of gardeners treat it as a short lived accent and replace it every few years rather than fight the climate. In a pot of gritty free draining mix it is far easier to keep. Do not enrich the planting hole either: backfill with the soil that came out of it and let the plant find its own way.

Cushion bush next to licorice plant

The other silver here is licorice plant, and they are not interchangeable. Helichrysum is soft, felted and sprawling, covers ground quickly, spills out of a pot and takes hard pruning without complaint. Cushion bush is rigid, architectural and self contained, holds a tight ball shape with no support and takes far more coastal blast. Choose Leucophyta when you want a silver form that reads as a shape in the bed, and a genuine local species for an exposed site. Choose Helichrysum when you want silver to trail over an edge and fill a gap in one season. For a flowering companion on the same dry bank, seaside daisy takes the same exposure.

Light trimming, and going very easy on fertiliser

Trim little and often through the warm months, taking the outer few centimetres to keep the mound tight and dense. The rule that matters is this: do not cut back into bare old wood, because it does not reliably reshoot from it and a hard rejuvenation cut usually leaves a permanent hole. Once a plant has opened out in the middle it is easier to replace than repair. Feeding is close to unnecessary. A light application of a low phosphorus native fertiliser in early spring is plenty, and generous feeding gives you soft, leggy growth that flops open and rots at the first humid week.

Choosing a size

This plant is available in 5 sizes, from 75mm up to 200mm, priced from $16.95 to $31.95 per plant. The size shown is the pot the plant arrives in, which is the rootball, not the height of the plant. These are younger plants, priced for planting in quantity, and they establish quickly once in the ground. Not sure which to choose? Read our guide to when to plant in Australia.