Rosmarinus officinalis 'Alba'

White Flowering Rosemary / White Rosemary

Botanical Name: Rosmarinus officinalis ‘Alba’
Family: Lamiaceae
Origin: Mediterranean region (cultivar selection)
Plant Type: Evergreen shrub (upright to softly spreading)

Overview

Perfectly suited to Adelaide’s Mediterranean climate, Rosmarinus officinalis ‘Alba’ is a tough, aromatic evergreen shrub prized for its soft white flowers and classic rosemary form. Flowering mainly from late winter through spring, and often again sporadically through the year, it provides gentle colour and strong sensory appeal when many gardens are still quiet. Like all rosemary, it thrives in heat, dry conditions, wind and poor soils, making it an outstanding choice for waterwise, coastal and low-maintenance gardens across South Australia. Its narrow grey-green foliage releases a strong, familiar herbal fragrance when brushed, while the neat, dense habit suits hedging, borders, pots and herb gardens.

Key Features

• Mature Size: 0.8–1.5 m H × 0.8–1.5 m W (upright, bushy shrub)
• Growth Rate: 20–40 cm per year under good conditions
• Foliage: Narrow, needle-like grey-green leaves; foliage may take on silvery or slightly bluish tints in dry or exposed conditions
• Flowers: Soft white to creamy-white flowers, mainly winter–spring with repeat flowering at other times
  
• Fragrance: Strongly aromatic foliage with classic rosemary scent; flowers lightly fragrant
• Seasonal Interest: Evergreen foliage year-round with peak white flowering in winter–spring
• Wildlife Value: Flowers attract bees and other beneficial pollinators
• Tolerance: Extremely drought tolerant once established; excellent heat and wind tolerance; coastal tolerant (first- and second-line); light frost hardy; dislikes heavy, waterlogged soils
• Planting Density: Hedges or borders: plant 60–80 cm apart; informal shrubs: allow 1–1.5 m spacing
• Pet Friendly: Generally regarded as safe and non-toxic

Where It Works Best

• Sunlight: Full sun essential for best growth, fragrance and flowering
• Soil: Free-draining sandy, loamy or gravelly soils; thrives in alkaline and limestone soils common across Adelaide
• Water Needs: Establishment: 1–2 deep soaks/week for 6–8 weeks. Established: very low water needs; occasional watering during extended heatwaves only
• Maintenance: Very low; light prune after flowering or as needed to maintain shape; avoid heavy feeding—no fertiliser required in most soils
• Lifespan: 10–25+ years in well-drained conditions
• Climate Zones: Ideal for Mediterranean and temperate SA — Adelaide Plains, coastal suburbs, Fleurieu Peninsula, Yorke Peninsula
• Soil pH: Neutral to alkaline; tolerates mildly acidic soils with good drainage

Landscape & Design Ideas

• Informal or clipped hedging for low borders and pathways
• Waterwise and Mediterranean-style gardens
• Coastal gardens exposed to wind and salt
• Herb and kitchen gardens near paths and alfresco areas
• Herb and kitchen gardens near paths and alfresco areas

Why You Will Love It

White rosemary offers all the toughness, fragrance and reliability of classic rosemary, paired with elegant white flowers that brighten the garden in winter and spring. Hardy, drought tolerant and beautifully aromatic, Rosmarinus officinalis ‘Alba’ is an easy-care essential for Adelaide gardens seeking structure, scent and year-round usefulness.