Gleditsia Triacanthos var. Inermis 'Shademaster'

Shademaster Honeylocust / Shademaster Locust Tree

Botanical Name: Gleditsia triacanthos var. inermis 'Shademaster'
Family: Fabaceae
Origin: North America (central & eastern USA)
Plant Type: Deciduous tree

Overview

‘Shademaster’ is a fast, reliable shade tree for South Australian streets and gardens. Thornless and tidy, it forms a broad, airy canopy of fine pinnate to bipinnate leaves that cast cool, dappled shade. Small spring flowers are subtle but nectar-bearing, and autumn brings a clear yellow foliage show. Superb for avenues, large lawns and low-water landscapes.

Key Features

• Mature Size: 10–15 m H × 8–12 m W (smaller with pruning/site limits)
• Growth Rate: 40-80 cm per year under good conditions
• Foliage: Fine, glossy light- to mid-green pinnate/bipinnate leaves; airy, elegant habit
• Flowers: Small greenish-yellow sprays in late spring; usually few pods on this cultivar
  
• Seasonal Interest: Cool summer shade; golden-yellow autumn colour; neat winter framework
• Wildlife Value: Flowers offer bee/pollinator interest; canopy provides bird shelter
• Tolerance: Drought-tolerant (once established), heat-tolerant, wind-tolerant, second-line coastal-tolerant; frost hardy; clay-tolerant (with drainage)
• Planting Density: Avenue/specimen: 6–10 m apart (≈ 1 tree per 36–100 m²), depending on desired canopy
• Pet Friendly: Yes — generally regarded as non-toxic; avoid ingestion of pods/seeds (may upset tummy)

Where It Works Best

• Sunlight: Full sun (essential for best form and colour)
• Soil: Well-drained loam, sandy loam or improved clay; copes with compaction and urban conditions
• 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: Mulch in spring; formative prune in winter to a balanced frame; light feed in early spring. Remove any thorny rootstock shoots if they appear
• Lifespan: 50–80+ years
• Climate Zones: Suited to temperate and Mediterranean SA gardens/streetscapes, including inland and many coastal suburbs (away from direct salt spray)
• Soil pH: Acid, Neutral, Alkaline — highly adaptable

Landscape & Design Ideas

• Avenues/driveways for uniform shade and light, open canopies
• Specimen on lawns where dappled shade is preferred over dense darkness
• Low-water streetscape plantings with lomandra, westringia and ornamental grasses

Why You Will Love It

A thornless, fast-establishing shade tree that thrives in heat, wind and tough urban soils. ‘Shademaster’ delivers graceful, filtered shade, dependable autumn colour and low maintenance — a high-value pick for SA homes and streets.