7 Common Landscape Design Mistakes Melbourne Homeowners Make

Learning from Others’ Mistakes

After three decades of landscape design in Melbourne’s north-east, we have seen—and occasionally been called to fix—the same mistakes repeated by enthusiastic homeowners. These aren’t just aesthetic disagreements. They are functional failures that cost time, money, and frustration.

Understanding these common errors helps you avoid them in your own garden, whether you’re working with a designer or tackling a DIY project.

Mistake #1: Ignoring Drainage

Water management is perhaps the most overlooked aspect of garden design, yet it is one of the most critical. Poor drainage leads to waterlogged plants, eroding paths, damaged retaining walls, and even impacts on house foundations.

What goes wrong:

• Reactive Clay Soils: Melbourne’s north-eastern suburbs are notorious for heavy clay soils that swell when wet and shrink when dry.
• Incorrect Slopes: Paving often slopes toward the house instead of away, directing stormwater into the foundations.
• Trapped Water: Garden beds frequently trap water against fences or masonry walls without relief points.
• Retaining Wall Failure: Walls are built without adequate backfill or “ag pipe” (agricultural pipe), causing them to bow under hydrostatic pressure.

How to get it right: You must ensure every hard surface falls away from structures. The National Construction Code generally looks for a minimum 1:100 gradient for soil, but we recommend a steeper 1:50 fall for paved areas to ensure rapid runoff during Melbourne’s sudden downpours.

Garden beds in clay soil need internal drainage or raised planting mounds. For retaining walls, never skip the drainage aggregate and ag pipe behind the wall. Water needs a clear path to the stormwater system or a legal discharge point.

Professional designers analyse water movement across the entire site. We design comprehensive drainage as an integral part of the landscape rather than an afterthought.

Mistake #2: Underestimating Mature Plant Size

That cute little tree from the nursery might be 12 metres tall and 8 metres wide at maturity. Plants in retail pots give little indication of their ultimate size, leading to expensive removal jobs later.

What goes wrong:

• Foundation Threats: Magnolia grandiflora (even the ‘Little Gem’ variety) is often planted too close to homes, where its aggressive root system can wreak havoc on footings and pipes.
• Service Interference: Trees are planted over sewer or water lines without checking their location first.
• Overcrowding: Shrubs outgrow their positions within two years, requiring constant pruning that ruins their natural shape.
• Blocked Views: Inappropriate species eventually block the very views they were meant to frame.

How to get it right: Research the mature size of every plant before committing. A 2023 arboriculture report highlights that tree roots can extend up to three times the width of the canopy, so spacing is non-negotiable.

Before you dig, use the “Before You Dig Australia” service to locate underground assets. If you need screening near a building, choose plants with less invasive root systems like Acmena smithii (Lilly Pilly) or specific Camellia varieties.

This is where professional plant knowledge pays dividends. We understand how plants behave over decades, not just how they look in nursery pots.

Mistake #3: Creating Unusable Spaces

Good garden design creates spaces sized for actual activities. Too often, we see outdoor areas that look nice on paper but don’t function in reality because the dimensions are just slightly off.

What goes wrong:

• Cramped Dining: Alfresco areas are often too small for a table and chair circulation, forcing guests to shuffle sideways.
• Awkward Steps: Steps with inconsistent risers (height) or runs (depth) create trip hazards.
• Narrow Paths: Side paths are frequently less than 900mm wide, making it impossible to move a wheelbarrow or bin comfortably.
• Unusable Lawns: Grassed areas are designed in odd, jagged shapes that are frustrating to mow.

How to get it right: Design around real furniture dimensions and human movement. Use this table as a guide for planning your entertaining zones:

Zone Type	Minimum Size	Comfortable Size
Dining (6 People)	3.5m x 3.5m	4.0m x 6.0m
Lounge Setting	3.0m x 3.0m	4.0m x 5.0m
Main Pathway	1.0m width	1.2m - 1.5m width
Service Path	0.9m width	1.2m width

Comfortable steps should have a riser between 150-170mm and a run of 280-350mm. We always measure your specific furniture and intended activities before locking in the floor plan.

Mistake #4: Choosing Form Over Function

It is tempting to choose materials and plants based purely on appearance, but gardens are functional spaces that must perform in Melbourne’s variable conditions.

What goes wrong:

• Slippery Surfaces: Honed Bluestone looks sleek but can be incredibly slippery when wet.
• Timber Bleed: Merbau decking is popular for its price, but it bleeds tannins heavily when wet, permanently staining light-coloured pavers or render below it.
• High-Maintenance Wood: Softwoods like treated pine rot quickly if in contact with ground moisture.
• Impractical Layouts: Designs that prioritise visual symmetry often ignore how people actually move through the space.

How to get it right: Always balance aesthetics with performance ratings. For paved areas exposed to rain, specify a “Sawn” or “Grit-blasted” finish on Bluestone to achieve a P4 or P5 slip rating (R11/R12).

If you choose timber decking, Spotted Gum is a Class 1 durable Australian hardwood that holds up better than many imports, though it still requires oiling. For a truly low-maintenance option, consider high-quality composite decking like Trex or Ekodeck, which resist fading and rotting.

Mistake #5: Neglecting the Relationship with the House

Your garden should feel like an extension of your home rather than a separate entity. Yet many designs fail to create this connection, leaving the transition feeling disjointed.

What goes wrong:

• Clashing Styles: A modern, minimalist garden often looks jarring against a Federation-style home.
• Level Disconnects: Large steps down from the back door sever the flow between indoor and outdoor living areas.
• Ignored Views: Key windows look out onto fences or sheds instead of feature plants.
• Threshold Issues: Failing to plan for drainage at the door threshold leads to water ingress during storms.

How to get it right: Start any garden design from the house outward. Stand in your kitchen, living room, and bedroom to see what the garden looks like from inside.

Aim for a flush threshold where possible to create seamless “step-free” access. To comply with the National Construction Code (NCC) for waterproofing, this usually requires a specific linear drain (like those from Stormtech) installed directly against the door track. We choose materials that complement your architecture without slavishly matching it.

Mistake #6: Underestimating Maintenance Requirements

Every garden requires maintenance, but the amount varies enormously based on design decisions. Underestimating these requirements leads to overwhelmed owners and declining gardens.

What goes wrong:

• Fussy Hedges: Planting English Box (Buxus sempervirens) requires trimming 3-4 times a year to stay sharp.
• Complex Lawns: Tiny strips of grass or sharp corners are impossible to mow efficiently.
• Water Features: Ponds without high-quality filtration systems quickly turn into algae swamps.
• Messy Trees: Planting deciduous trees near gutters or pools creates a massive annual cleanup job.

How to get it right: Be honest about how much time you will realistically spend on garden maintenance. If you are busy, choose “low maintenance” plants like Lomandra ‘Lime Tuff’ or Rhaphiolepis, which look good year-round with minimal intervention.

Keep lawn shapes simple and continuous for easy mowing. We often recommend replacing small, difficult-to-mow grass patches with groundcovers or permeable paving. A slightly simpler garden that you can actually maintain is worth far more than a complex one that becomes a burden.

Mistake #7: Failing to Consider All Seasons

Melbourne has distinct seasons, and a garden designed only for spring and summer can become dreary through autumn and winter.

What goes wrong:

• Winter Bareness: Relying too heavily on herbaceous perennials leaves you with bare earth from May to August.
• Skeletons: Deciduous trees planted for summer shade can look stark and uninviting in winter if they lack structural beauty.
• Mud: Grass paths turn to mud baths in winter, making parts of the garden inaccessible.
• Lack of Winter Color: The garden becomes a sea of grey and brown during the colder months.

How to get it right: Include plants that provide interest in every season. Camellia sasanqua hedges bloom in autumn and early winter, providing colour when everything else is fading. Hellebores (Winter Rose) and Winter Sweet (Chimonanthus praecox) thrive in Melbourne’s cooler months.

Think about how the garden will be used year-round. We often include a fire pit area with crushed rock or paving so you can enjoy the outdoors even when the grass is wet.

The Value of Getting It Right First Time

All these mistakes share a common thread: they are easier and cheaper to avoid than to fix. Removing poorly placed trees, re-laying drainage, or demolishing undersized paving is expensive and disruptive.

Professional landscape design is not just about creating attractive drawings. It is about bringing experience and foresight to prevent costly errors. A designer who has seen hundreds of gardens knows what works and what fails.

Whether you engage a professional or proceed yourself, take time at the planning stage to think through these common pitfalls. Your future self—and your garden—will thank you.

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Want to ensure your garden project avoids common mistakes? Contact us for professional design that gets it right the first time.