What to Plant Around a Crepe Myrtle: Best Companion Plants for Australian Gardens

What to Plant Around a Crepe Myrtle: Best Companion Plants for Australian Gardens

Crepe myrtles (Lagerstroemia spp.) are a favourite in Australian gardens for their stunning summer blooms, striking autumn foliage and attractive winter bark. But to make the most of these deciduous trees, underplanting them thoughtfully can create a layered, low-maintenance display. If you’re searching for what to plant around a crepe myrtle, focus on companions that match its preferences: full sun, well-drained soil, moderate watering once established and tolerance for our variable climates.

In this guide, we’ll cover why companion planting works, top choices suited to Australian conditions (especially subtropical, Mediterranean and warm temperate zones) and practical tips for success. These selections emphasise drought-tolerant, non-competitive plants that suppress weeds, improve soil health and enhance aesthetics without overwhelming the tree.

Why Plant Companions Around Crepe Myrtles?

Crepe myrtles grow 3–10 metres tall depending on the variety, with a spreading canopy and surface roots. Planting underneath provides multiple benefits:

• Weed suppression: A living mulch layer reduces competition from grasses and other invasives.
• Soil improvement: Deep-rooted companions aerate soil and add organic matter as leaves drop.
• Visual appeal: Fills the ‘bare legs’ look during the tree’s dormant winter phase.
• Microclimate enhancement: Groundcovers retain moisture and cool roots in hot Aussie summers.
• Pest deterrence: Diverse planting can confuse pests like aphids, which sometimes plague crepe myrtles.

Choose plants for USDA-equivalent zones 9–11 (most of coastal Australia from Sydney northwards and inland to drier areas). In cooler spots like Melbourne, opt for hardier varieties like L. indica ‘Natchez’ and frost-tolerant companions.

Key Considerations Before Planting

• Light: Crepe myrtles demand 6+ hours of sun daily. Skip shade-lovers.
• Water: Drought-tolerant once established; avoid thirsty plants.
• Soil: Neutral to slightly acidic (pH 5.5–7.5), free-draining. Amend clay soils with compost.
• Spacing: Keep companions 30–50 cm from the trunk to avoid root competition.
• Size control: Low-growers under 1 metre prevent shading the lower trunk.

Prepare the area by mulching 10 cm deep with organic matter, then plant into this. Water deeply but infrequently to establish.

Best Groundcovers for Under Crepe Myrtles

Groundcovers form a carpet that mimics natural forest floors, perfect for crepe myrtles’ subtropical origins.

• Dichondra repens (Kidney Weed): Native Aussie superstar. Emerald-green foliage spreads 20–30 cm high, thrives in sun/part shade, drought-tolerant. Handles light foot traffic and frosts to -5°C. Plant 20 cm apart for quick coverage.
• Scaevola aemula (Fairy Fan Flower): Tough coastal native with purple fan blooms year-round. Grows 20–30 cm, loves full sun and poor soils. Butterfly magnet, salt-tolerant for seaside gardens.
• Brachyscome multifida (Cut-leaf Daisy): Delicate mauve daisy flowers on fine foliage. 20 cm high, ultra-drought hardy, suits arid zones. Prune lightly post-bloom.
• Mondo grass (Ophiopogon japonicus): Strappy evergreen, 20–30 cm. Tolerates dry shade under the canopy edge but prefers sun. Low-maintenance divider for paths.

These handle summer heatwaves and require minimal water after year one.

Perennials and Ornamental Grasses

For seasonal colour pops without height, these add texture and movement.

• Gaura lindheimeri: Airy white/pink wands dance in breeze, 60–90 cm. Full sun lover, drought-proof, blooms spring–autumn. Cut back in winter.
• Salvia species (e.g., S. microphylla, S. greggii): Velvety red/purple spikes attract bees. 50–80 cm, extremely dry-tolerant. Deadhead for repeats; suits hot inland areas.
• Coreopsis verticillata (Tickseed): Golden yellow flowers non-stop. 45 cm, thread-like foliage. Self-seeds mildly, frost-hardy to zone 8.
• Lomandra hystrix (Mat Rush): Native grass-like perennial, 60 cm. Lime-green straps, bird-friendly seedheads. Ultra-tough for sandy or clay soils.
• Dianella caerulea (Blue Flax Lily): Strappy native with blue berries. 60 cm, shade-tolerant at canopy edge. Edible fruit for wildlife.

Mix these for year-round interest: grasses for winter structure, perennials for summer fireworks.

Small Shrubs for Layered Effect

For subtle height variation (under 1.5 m), these frame the trunk without competing.

• Westringia fruticosa (Coastal Rosemary): Native grey-green shrub, 1 m. White flowers, wind/drought/salt tolerant. Prune to shape.
• Callistemon viminalis ‘Little John’ (Bottlebrush dwarf): Compact 1 m, red brushes. Full sun, attracts lorikeets.
• Grevillea ‘Superb’ hybrids*: Low-spreading 1 m, spider flowers in pinks/reds. Honeyeater haven, phosphorus-sensitive so use native mix.

Space 1 m from trunk; these stabilise soil on slopes.

Bulbs and Annuals for Seasonal Flair

Tuck in spring-flowering bulbs for winter colour when crepe myrtles are bare.

• Narcissus (Daffodils): Naturalise under trees. ‘Ice Follies’ suits mild frosts.
• Crocus and Iris reticulata: Early bursts of purple/yellow.
• Annuals like Portulaca or Gazania for hot, dry filler spots.

Plant bulbs 10–15 cm deep in autumn.

What NOT to Plant Around Crepe Myrtles

Avoid these pitfalls:

• Invasive grasses like Kikuyu or Paspalum – smother roots.
• Thirsty plants e.g., Rhododendrons, Camellias – compete for water.
• Tall shade-casters like Agapanthus or Cordyline – block sun.
• Heavy feeders like Roses – deplete nutrients.
• Frost-tender exotics in cool climates.

Planting and Maintenance Tips

1. Timing: Plant in autumn/spring for root establishment before summer heat.
2. Preparation: Fork in compost/yum yum mix (low-phosphorus for natives). Mulch 7–10 cm deep, keeping clear of trunk.
3. Layout: Central circle bare around trunk (1 m radius), then rings of groundcover, perennials outward.
4. Watering: 20–30 L/week per sq m first summer, then rain-dependent.
5. Fertiliser: Slow-release native blend in spring. Avoid high-nitrogen.
6. Pruning: Trim companions post-bloom; crepe myrtle after flowering (never spring).
7. Pests: Monitor for powdery mildew; good airflow from underplanting helps.

In pots or small gardens, dwarf crepe myrtles like ‘Pocomoke’ pair with trailing Petunias or Succulents.

Regional Australian Advice

• Queensland/NT (hot/humid): Prioritise natives like Scaevola, Lomandra for humidity tolerance.
• Sydney/Coastal NSW: Mix Dichondra with Salvias for salt winds.
• Adelaide/Perth (Mediterranean): Gaura, Coreopsis shine in dry summers.
• Melbourne/Victoria: Hardy options like Brachyscome, Daffodils for frosts.
• Inland dry: Lomandra, Westringia for water-wise.

Create Your Dream Crepe Myrtle Garden

By selecting what to plant around a crepe myrtle wisely, you’ll craft a vibrant, sustainable garden that celebrates Australia’s diverse climates. Start small – a ring of Dichondra and Gaura transforms any specimen. Experiment, observe and adjust; healthy soil yields happy plants.

Word count: ~1150. Happy gardening!

Images suggestion: Include photos of planted examples, before/afters.