Cerastium tomentosum 'Snow In Summer'

Snow-In-Summer

Botanical Name: Cerastium tomentosum ‘Snow-in-Summer’
Family: Caryophyllaceae
Origin: Southern Europe (rocky/alpine and coastal cliffs)
Plant Type: Evergreen to semi-evergreen groundcover (prostrate, spreading)

Overview

A tough, sun-loving silver carpet that smothers itself in pure white flowers in late spring–early summer—like a dusting of snow. Superb for Adelaide/SA in full sun and sharp drainage: rockeries, retaining walls, path edgings and spill-over edges. Handles heat and wind once established; happiest on the Adelaide Plains and coastal second-line sites where soils are lean and free-draining.

Key Features

• Mature Size: 0.1–0.15 m H × 0.6–1.0 m W (spread)
• Growth Rate: 30-60 (spread) cm per year under good conditions
• Foliage: Small, silvery-grey, felted leaves forming dense, cascading mats
• Flowers: Masses of bright white, starry blooms mainly late spring–early summer (spot flowers later)
  
• Seasonal Interest: Year-round silver foliage; dramatic spring “snow” display
• Wildlife Value: Nectar for bees and other pollinators
• Tolerance: Drought-tolerant once established, heat- and wind-tolerant; second-line coastal OK (avoid heavy salt spray/front-line); light–moderate frost hardy; dislikes winter waterlogging
• Planting Density: 6–9 plants per m² for fast cover (3–4/m² for slower, larger clumps)
• Pet Friendly: Generally non-toxic; ingestion of any plant may upset pets

Where It Works Best

• Sunlight: Full sun (best silver and flowering); tolerates light part shade but mats open up
• Soil: Free-draining sands or sandy/loam; thrives on neutral–alkaline (calcareous) SA soils; raise/mound on 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); minimal in winter—keep on the dry side
• Maintenance: Shear back lightly after flowering to keep tight and encourage a fresh silver flush; remove spent stems; avoid heavy fertilising (too rich = floppy/green). Divide/refresh clumps every 3–4 years if they thin in the centre
• Lifespan: 5–10+ years in well-drained sites
• Climate Zones: Temperate & Mediterranean SA—excellent on the Adelaide Plains and second-line coastal areas; protect from prolonged winter wet in Hills gardens
• Soil pH: Neutral to alkaline (tolerates slightly acidic)

Landscape & Design Ideas

• Rockeries, retaining walls & spill-over edges for a bright silver cascade
• Path edgings and between stepping stones for a tidy, low carpet
• Gravel/Mediterranean borders with lavender, rosemary and ornamental grasses

Why You Will Love It

An effortless silver groundcover that glows in Adelaide sun and delivers a show-stopping spring snow of flowers—low water, low fuss, high impact.