You've invested time and money into installing beautiful garden edging—now how do you keep it looking its best? While modern edging materials are designed for durability, a little regular maintenance goes a long way toward extending lifespan and maintaining that fresh-installed appearance. This guide covers maintenance essentials for all major edging types commonly used in Australian gardens.
Why Maintenance Matters
Even the most durable garden edging benefits from regular attention. Without maintenance, you might encounter shifting and movement caused by soil expansion and contraction, grass and weeds growing over or through edging, rust or degradation in metal and plastic materials, rot and pest damage in timber, and accumulated dirt obscuring the edging's appearance.
The good news is that most maintenance tasks are quick and simple. A few minutes of attention each season can prevent larger problems and keep your garden borders looking sharp for decades.
Steel Edging Maintenance
Steel edging is one of the lowest-maintenance options available, but it still benefits from periodic attention, particularly in the Australian climate where intense sun and occasional heavy rains can stress any material.
Galvanised Steel
Galvanised steel is protected by a zinc coating that prevents rust. Your maintenance focus should be on preserving this coating and addressing any damage promptly.
- Inspect for scratches or chips in the galvanised coating
- Check stakes for looseness and re-secure if needed
- Clear debris that accumulates against the edging
- Trim grass and roots growing against or over the edge
- Verify that connections between sections remain secure
If you notice scratches or chips in the galvanised coating, treat them promptly with a cold galvanising spray (available from hardware stores). This prevents rust from developing and spreading beneath the intact coating.
For coastal areas where salt spray is present, rinse your edging with fresh water periodically to prevent salt buildup, which can accelerate corrosion even on galvanised products.
Corten Steel
Corten steel is virtually maintenance-free because its rusty patina is an intentional feature rather than a problem. The rust layer actually protects the underlying steel from further corrosion.
Your main maintenance tasks with Corten are purely aesthetic: remove any debris that accumulates against the edging, and trim vegetation that grows up against it. Some gardeners like to brush off loose rust flakes in the early months as the patina develops, but this is optional.
One consideration with Corten is rust staining. Water running off Corten steel can leave rust-coloured stains on adjacent concrete or paving. If this concerns you, consider the placement of your edging relative to hard surfaces, or be prepared to clean stains with appropriate concrete cleaners.
Plastic Edging Maintenance
Plastic edging requires more frequent attention than steel, primarily because it's more prone to movement and UV degradation. However, maintenance is straightforward and takes just minutes.
Check plastic edging every few months for signs of shifting or heaving. Australian soil conditions, particularly reactive clay soils common in Melbourne and Adelaide, can push plastic edging out of position during seasonal wetting and drying cycles. If sections have moved, simply push them back into place and add additional stakes if needed.
Inspect for cracks, particularly in areas that receive full sun. UV degradation causes plastic to become brittle over time, and once cracking begins, it spreads quickly. Replace damaged sections promptly—leaving cracked edging in place allows grass and weeds to grow through the gaps, creating more work later.
Keep mulch piled up against plastic edging where possible. The mulch shields the plastic from direct UV exposure, significantly extending its lifespan. Just ensure the edging top remains visible to maintain its functional border.
Clean plastic edging occasionally with a hose or damp cloth to remove dirt and algae buildup. This is purely cosmetic for most plastic edging, but regular cleaning helps you spot any developing damage.
Timber Edging Maintenance
Timber requires the most maintenance of common edging materials, but many gardeners find the natural aesthetic worth the extra effort. The key is preventing rot and pest damage while maintaining the wood's appearance.
Regular Inspection
Inspect timber edging at least twice yearly—ideally at the start and end of the wet season. Look for soft or spongy areas that indicate rot beginning, insect damage or bore holes, splitting or cracking, loose fixings or stakes, and ground contact areas where moisture accumulates.
Preventative Treatments
Even pressure-treated timber benefits from additional protection. Apply a quality timber preservative or decking oil annually, paying particular attention to end grain and any cut surfaces. These are the areas most vulnerable to moisture penetration and rot.
Ensure drainage around timber edging is adequate. Standing water against timber is a recipe for rot. If you notice water pooling, consider improving drainage or raising the edging slightly.
In termite-prone areas (much of Australia), monitor timber edging carefully for signs of termite activity. While treated timber is resistant, it's not immune. Consider termite barriers during installation or choose alternative materials if termite risk is high in your area.
Dealing with Rot
If you catch rot early, you may be able to treat it with a timber hardener product, then seal and protect the affected area. However, advanced rot usually requires section replacement. The advantage of timber edging is that individual pieces can often be replaced without disturbing the entire installation.
Stone and Concrete Edging Maintenance
Stone and concrete edging are the most durable options and require minimal maintenance. However, they're not entirely maintenance-free.
Weed growth is the primary concern with stone edging. Weeds can establish in gaps between stones or in any accumulation of soil and debris. Remove weeds promptly before they become established, and consider applying a non-residual herbicide to gaps if weeds are persistent.
Check periodically for stones that have shifted or settled. Australian soil movement can push stones out of position over time. Re-bedding shifted stones usually just requires lifting them, adding or removing base material, and resetting.
For concrete sleepers, inspect for cracks, particularly in areas with reactive soils. Small cracks are usually cosmetic, but expanding cracks may indicate soil movement issues that need addressing.
Clean stone and concrete edging occasionally with a stiff brush and water to remove accumulated dirt and algae. For stubborn stains, a pressure washer on a low setting works well, but be careful not to dislodge mortar or joint material.
General Maintenance Tips for All Edging Types
Regardless of material, some maintenance practices benefit all garden edging:
Keep edges clear. Regularly trim grass and vegetation that grows up against your edging. This prevents organic matter from accumulating against the edging and keeps borders looking crisp. A half-moon edger or string trimmer makes quick work of this task.
Maintain mulch levels. Top up mulch in garden beds annually. Proper mulch levels (50-75mm) help hide the base of your edging while protecting plant roots and suppressing weeds. Avoid piling mulch so high that it spills over onto the lawn.
Address soil erosion. If soil is washing away from either side of your edging, address the drainage issue causing it. Eroded soil exposes edging foundations and can lead to movement and instability.
Fix problems promptly. Small issues become big problems when ignored. A slightly loose stake is a 30-second fix; a completely destabilised section requires much more work. Regular walks around your garden help you catch issues early.
Creating a Maintenance Schedule
The easiest way to stay on top of edging maintenance is to incorporate it into your regular garden routine. Here's a simple schedule:
Monthly: Quick visual inspection while doing other garden tasks. Look for obvious issues like shifted sections or damage.
Seasonally: More thorough inspection. Trim grass against edging, check stakes and fixings, clean if needed.
Annually: Complete assessment of edging condition. Apply treatments to timber. Address any accumulated issues. Top up mulch levels.
With this simple approach, your garden edging will continue to enhance your outdoor space for years to come, providing lasting value for your initial investment.