Ground Cover Under Crepe Myrtle: Top Low-Maintenance Choices for Aussie Gardens

Why Choose Ground Cover Under Crepe Myrtle?

Crepe myrtles (Lagerstroemia spp.) are a staple in Australian gardens, prized for their vibrant summer blooms, striking autumn colour and attractive bark. These deciduous trees or large shrubs thrive in warm climates from subtropical Queensland to Mediterranean-like regions in Western Australia and South Australia. However, the bare soil beneath their canopy can lead to weed problems, erosion and water loss, especially during our hot, dry summers.

Planting ground cover under crepe myrtle offers multiple benefits:

• Weed suppression: Dense mats outcompete unwanted plants.
• Moisture retention: Reduces evaporation in sandy or clay soils common across Australia.
• Erosion control: Stabilises soil around shallow crepe myrtle roots.
• Aesthetic appeal: Creates layered garden designs with contrasting foliage and flowers.
• Microclimate improvement: Low-growing plants provide dappled shade tolerance and mulch-like effects.

In Australian conditions, select drought-tolerant, low-water options that handle full sun to part shade under the canopy. Crepe myrtles drop leaves in winter, so evergreen ground covers maintain year-round interest. Avoid water-hungry plants that compete with the tree’s roots.

Top Ground Cover Recommendations for Under Crepe Myrtle

Here are proven performers suited to Australian climates (USDA zones 9-11 equivalent, or cooler with protection). All are available at local nurseries and adapt well to our variable soils and rainfall.

1. Kidney Weed (Dichondra repens)

This native Aussie superstar forms a lush, bright green carpet, perfect under crepe myrtles. It tolerates dappled shade, dry spells and light foot traffic.

• Height: 5-10 cm.
• Spread: Up to 1 m.
• Climate suitability: All mainland states; frost-tolerant to -5°C.
• Care notes: Plant 30 cm apart in spring. Minimal watering once established. Mow occasionally for tidiness.
• Why it works: Non-invasive roots coexist with crepe myrtle; small white flowers in spring add charm.

2. Creeping Myoporum (Myoporum parvifolium)

A tough native ground cover with fine, grey-green leaves and tiny white-star flowers. Excellent for arid zones.

• Height: 10-15 cm.
• Spread: 1-2 m.
• Climate suitability: Ideal for inland NSW, VIC, SA and WA; handles heatwaves and poor soils.
• Care notes: Space 50 cm apart. Drought-proof after 12 months; prune lightly if leggy.
• Why it works: Salt and wind tolerant for coastal gardens; suppresses weeds effectively under open-canopied crepe myrtles.

3. Native Violet (Viola hederacea)

Delicate purple flowers on trailing stems make this a pretty choice for shaded spots under denser crepe myrtles.

• Height: 5-10 cm.
• Spread: 50 cm.
• Climate suitability: Humid subtropics (QLD, northern NSW) to temperate areas; prefers moist but well-drained soil.
• Care notes: Plant 20 cm apart in autumn. Mulch with 5 cm organic matter; water weekly in first summer.
• Why it works: Self-seeds gently for natural spread; contrasts beautifully with crepe myrtle’s bark.

4. Purple Fan Flower (Scaevola aemula)

Vibrant mauve fan-shaped blooms from spring to autumn. A coastal favourite.

• Height: 20-30 cm.
• Spread: 1 m.
• Climate suitability: Eastern seaboard and WA coasts; full sun lover but shade-tolerant underneath.
• Care notes: 40 cm spacing. Tip-prune after flowering to encourage bushiness.
• Why it works: Butterfly attractor; resilient to salty winds and sandy soils common under street-planted crepe myrtles.

5. Running Postman (Kennedya rubicunda)

Red tubular flowers on twining stems for a wildflower look.

• Height: 20 cm (trailing).
• Spread: 2 m.
• Climate suitability: Temperate to subtropical; good for Sydney basins and Tassie.
• Care notes: Plant in poor soil; space 1 m. Low phosphorus fertiliser only.
• Why it works: Nitrogen-fixing, improving soil for crepe myrtles; evergreen in mild areas.

Other Options

• Ice Plant (Aptenia cordifolia): Succulent for hot, dry spots (hot pink flowers).
• Lomandra hystrix ‘LH Green’: Strappy native for tougher, higher-traffic areas (30-40 cm high).
• Brachyscome multifida: Daisy-like flowers for sunny, inland gardens.

Avoid invasives like ivy or gazania, which can overwhelm crepe myrtle roots.

How to Plant Ground Cover Under Crepe Myrtle

Timing is key: Plant in autumn or early spring to avoid summer heat stress.

1. Prepare the site: Clear weeds within 1-2 m of the trunk. Loosen soil to 20 cm deep, incorporating compost if clay-heavy (common in SA/VIC). Avoid digging near roots.
2. Soil amendment: Add gypsum for heavy clays or aged manure for sandy soils. Aim for pH 6-7, matching crepe myrtle preferences.
3. Planting: Dig holes twice the pot width, 30-50 cm apart depending on variety. Water deeply (20 L per plant) and mulch with 5-7 cm pine bark or sugar cane to 10 cm from trunk.
4. Irrigation: Deep water every 5-7 days for 3 months, then taper off. Drip irrigation works best in drier regions like Perth.

In pots? Use 140 mm natives for instant colour under smaller crepe myrtles.

Maintenance Tips for Long-Term Success

• Watering: Once established, most need only rainfall. Supplement during 40°C+ heatwaves or El Niño droughts.
• Fertilising: Low-phosphorus native mix (e.g. 5 g/m²) in spring. Crepe myrtles appreciate the same.
• Pruning: Trim spent flowers; shear kidney weed annually for density.
• Pest watch: Check for aphids or scale (treat with eco-oil). Ground covers deter powdery mildew by improving air flow.
• Mulching refresh: Top up 5 cm yearly to mimic natural bush floors.

In frosty areas (e.g. inland NSW), mulch heavily in winter. For wet tropics, ensure good drainage to prevent root rot.

Common Mistakes to Avoid

• Overwatering: Leads to shallow roots and fungal issues in humid QLD.
• Planting too close to trunk: Causes rot; leave 50 cm bare circle.
• High-nitrogen fertilisers: Promotes soft growth vulnerable to pests.
• Ignoring climate: No succulents in wet shade; no shade-lovers in full sun.
• Neglecting weeds initially: Spot-spray glyphosate carefully before planting.

Designing Your Crepe Myrtle Understorey

Layer for impact: Ground covers at base, mid-level perennials like dianella (30 cm), then the crepe myrtle canopy. In small gardens, use kidney weed for a seamless lawn alternative. For bold colour, mix scaevola with creeping boobialla (Myoporum).

These combos create sustainable, water-wise gardens that shine in Australia’s diverse climates. Expect full coverage in 12-18 months, transforming barren patches into thriving ecosystems.

Ready to green up under your crepe myrtle? Start with natives from your local specialist nursery for best adaptation.