Prostanthera Ovalifolia Compacta

Compact Mint Bush

Botanical Name: Prostanthera ovalifolia ‘Compacta’
Family: Lamiaceae
Origin: Eastern Australia
Plant Type: Evergreen shrub

Overview

A fragrant, floriferous native shrub that brings colour, scent, and softness to South Australian gardens. Prostanthera ovalifolia ‘Compacta’ forms a neat, rounded bush with aromatic foliage and masses of purple-mauve flowers in spring. Adaptable and hardy once established, it performs beautifully in Adelaide’s Mediterranean climate, handling dry summers, light frost, and even coastal winds when sheltered. Perfect for native gardens, mixed borders, or sensory plantings, it adds both structure and a burst of seasonal bloom.

Key Features

• Mature Size: 1.0–1.5 m H × 0.8–1.2 m W — compact and naturally rounded
• Growth Rate: 20-40 cm per year under good conditions
• Foliage: Small oval, mid-green aromatic leaves; foliage emits a pleasant minty–eucalypt scent when brushed or warmed by the sun; tips may bronze slightly in cold or high sun
• Flowers: Abundant mauve to purple tubular blooms in mid- to late spring (often with a lighter second flush in autumn)
  
• Seasonal Interest: Spring floral display; aromatic evergreen foliage year-round
• Wildlife Value: Attracts bees, butterflies, and native pollinators; provides shelter for small birds
• Tolerance: Drought-, heat-, and wind-tolerant once established; light frost-hardy; coastal-tolerant in protected sites
• Planting Density: 1–2 plants per m² for individual shrub spacing or small groupings
• Pet Friendly: Non-toxic to cats and dogs

Where It Works Best

• Sunlight: Full sun to part shade — best flowering and compact growth in full sun; tolerates part shade, especially in hot inland sites
• Soil: Free-draining sandy, loamy, or gravelly soils; tolerates poor soils if drainage is good; dislikes heavy, waterlogged ground
• Water Needs: Establishment: 2 deep soaks/week for 8–12 weeks. Established: deep soak every 10–14 days in summer; monthly in winter if dry
• Maintenance: Low maintenance – light prune after flowering to maintain shape and encourage fresh growth; avoid hard pruning into old wood; apply slow-release native fertiliser in early spring
• Lifespan: 8–12+ years with minimal care
• Climate Zones: Mediterranean and temperate – thrives across Adelaide Hills, plains, Fleurieu Peninsula, and coastal SA
• Soil pH: Neutral to slightly acidic, tolerates mild alkalinity

Landscape & Design Ideas

• Native Gardens: Use as a feature shrub or repeat planting for seasonal purple displays and aromatic foliage
• Cottage & Coastal Gardens: Adds softness and perfume; combine with Grevillea ‘Winpara Gem’, Westringia ‘Mundi’, or Leucophyta ‘Silver Nugget
• Mixed Shrub Borders: Blends beautifully with Lavender, Rosemary, or Kangaroo Paw for textural and colour contrast
• Containers & Courtyards: Excellent in large pots for alfresco spaces where scent and seasonal colour enhance the atmosphere

Why You Will Love It

‘Compacta’ brings vibrant spring colour and aromatic foliage to South Australian gardens — hardy enough for coastal winds, drought, and heat, yet soft and scented like a cottage plant. Perfect for borders, native designs, and sensory gardens, it’s a no-fuss shrub that delivers fragrance, wildlife value, and year-round appeal.