Centaurea 'Silver Fountain'

Silver Fountain / Velvet Centaurea

Botanical Name: Centaurea cineraria ‘Silver Fountain’ (syn. sometimes sold as C. gymnocarpa ‘Silver Fountain’)
Family: Asteraceae
Origin: Mediterranean (southern Italy coastal cliffs; hort. selection)
Plant Type: Evergreen to semi-evergreen, short-lived perennial (silvery subshrub)

Overview

A striking silver foliage perennial forming wide, arching clumps with a velvety feel. In Adelaide/SA it thrives in full sun and well-drained, preferably alkaline soils, shrugging off heat and coastal wind. Spring–summer brings tufty purple/mauve cornflower-like blooms that bees adore—grow it for the luminous foliage first, flowers second.

Key Features

• Mature Size: Typically 0.4–0.8 m H × 0.6–1.0 m W in SA gardens; can reach ~1–1.5 m in ideal conditions
• Growth Rate: 20-40 (spread) cm per year under good conditions
• Foliage: Highly dissected, suede-textured silver-grey leaves in fountain-like clumps; brightest in full sun
• Flowers: Purple/mauve tufts mainly spring–summer (occasional off-season flush)
  
• Seasonal Interest: Year-round silver structure; spring–summer flower accents
• Wildlife Value: Nectar for bees and butterflies
• Tolerance: Drought and heat tolerant once established; wind & second-line coastal tolerant; light frosts OK—avoid winter waterlogging. Prefers alkaline/free-draining soils
• Planting Density: Borders: 3 per metre (≈ 30–40 cm centres). Mass: 3–5 plants/m². Containers: 25–35 cm pots; up-pot as clumps widen
• Pet Friendly: Generally non-toxic; ingestion of any plant may upset pets

Where It Works Best

• Sunlight: Full sun (best colour/shape); light part shade reduces silvering
• Soil: Free-draining sandy/loam; thrives on neutral–alkaline (calcareous) SA soils; mound on heavy clay to avoid winter wet
• Water Needs: Establishment: 2 deep soaks/week for 8–12 weeks. Established: deep soak every 2-3 weeks in summer (weekly in heatwaves); monthly in winter if dry
• Maintenance: Lightly trim after flowering; hard cut-back by ~30–40% in late autumn to keep dense; remove tired leaves; avoid heavy fertiliser (a light organic feed in spring is ample)
• Lifespan: 3–5+ (short-lived perennial; easy to renew from cuttings)
• Climate Zones: Temperate & Mediterranean SA—excellent on Adelaide Plains and coastal sites; protect from severe Hills frosts
• Soil pH: Neutral to alkaline (tolerates slightly acid)

Landscape & Design Ideas

• Silver contrast in gravel/xeric borders and Mediterranean schemes
• Coastal plantings with Convolvulus cneorum, rosemary and grasses
• Containers/front-of-border mounds as a bright, low-water accent

Why You Will Love It

A tough, heat- and drought-tolerant silver highlight that looks couture with almost anything—perfect for Adelaide gardens chasing sparkle, texture and low fuss.