Agapanthus orientalis 'Queen Mum'

African Lily / Lily of the Nile

Botanical Name: Agapanthus orientalis ‘Queen Mum’
Family: Amaryllidaceae
Origin: South Africa (garden cultivar)
Plant Type: Evergreen clump-forming perennial (strappy foliage)

Overview

Agapanthus orientalis ‘Queen Mum’ is a large, elegant agapanthus cultivar prized for its oversized bi-colour flower heads and bold architectural presence. Perfectly suited to Adelaide’s Mediterranean climate, it forms strong evergreen clumps of glossy strappy foliage and produces tall stems topped with striking white flowers flushed with soft blue at the base, giving the blooms a distinctive two-tone effect.

Flowering mainly through summer, ‘Queen Mum’ is tougher and more vigorous than dwarf forms, handling heat, wind, drought and coastal exposure once established. Its scale and drama make it ideal for feature borders, mass plantings, driveways, and large containers across South Australia, where long-lived structure and low maintenance are key.

Key Features

• Mature Size: 0.7–1.0 m H × 0.6–0.8 m W (foliage); flower stems to 1.2–1.4 m
• Growth Rate: 25–40 cm per year under good conditions
• Foliage: Evergreen, broad glossy mid- to deep-green strappy leaves forming a bold, upright clump
• Flowers: Large rounded umbels of white flowers with soft blue bases; produced mainly summer, with occasional late-season repeat flowering
• Fragrance: Not fragrant
• Seasonal Interest: Strong evergreen structure year-round with dramatic summer floral display
• Wildlife Value: Nectar-rich blooms attract bees and pollinators; dense clumps provide light shelter for beneficial insects
• Tolerance: Drought tolerant once established; excellent heat and wind tolerance; light–moderate frost hardy; tolerant of coastal conditions (second-line coastal); copes well with reflected heat
• Planting Density: Borders/feature planting: 1 per 0.6–0.8 m; Borders/feature planting: 1 per 0.6–0.8 m; Mass planting: space 60–80 cm apart
• Pet Friendly: Generally regarded as non-toxic; sap may irritate sensitive skin or pets—discourage chewing

Where It Works Best

• Sunlight: Full sun to part shade (best flowering in full sun)
• Soil: Well-drained loam, sandy loam or improved clay soils; adaptable to most Adelaide garden soils
• Water Needs: Establishment: 2 deep soaks/week for 8–12 weeks. Established: deep soak every 2–3 weeks in summer (weekly in heatwaves); minimal water in winter
• Maintenance: Remove spent flower stems at base after flowering; divide clumps every 3–5 years in late winter or early spring to maintain vigour; apply slow-release fertiliser in early spring
• Lifespan: 15–25+ years (long-lived perennial)
• Climate Zones: Ideal for temperate and Mediterranean South Australia — Adelaide Plains, Fleurieu Peninsula, Yorke Peninsula, sheltered coastal areas
• Soil pH: Neutral to slightly alkaline; very adaptable if drainage is good

Landscape & Design Ideas

• Bold summer feature plant in mixed borders
• Mass planting for strong architectural impact along driveways and verges
• Large containers for courtyards and alfresco spaces
• Pair with Lomandra, ornamental grasses, Dietes or silver-foliage plants
• Excellent for coastal and modern Mediterranean-style gardens

Why You Will Love It

‘Queen Mum’ delivers show-stopping summer flowers, evergreen structure and outstanding toughness in Adelaide conditions. Bigger and bolder than standard agapanthus, it’s a long-lived, low-maintenance plant that brings elegance, scale and reliability to South Australian gardens year after year.