Concrete edging, borders, and kerbing are the finishing details that define garden beds, driveways, paths, and property boundaries. When they’re in good condition, they’re largely invisible, they just work. When they’re cracked, heaved, crumbling, or overgrown, they draw attention to themselves and drag down the overall presentation of the property. On the Central Coast, where landscaping and outdoor presentation matter a great deal, particularly in the prestige suburbs of Terrigal and Avoca Beach, but also in presentation-conscious new estates, tired concrete edging is a common low-priority maintenance item that gets noticed by buyers, tenants, and visitors even when you’ve stopped seeing it.
Quick Answer (BLUF)
Concrete edging and borders can be refreshed by three main methods: grinding and resealing (for sound but aesthetically tired edging), crack filling and repainting with a concrete coating (for cracked but otherwise intact edging), or removal and replacement (for heaved, broken, or structurally failed edging). Most residential refresh jobs fall into the first or second category and are cost-effective DIY or trade jobs that make a significant visual difference.
Types of Concrete Edging and Borders
Poured Concrete Kerbing
The most common residential form, a continuous poured concrete strip 100-150 mm high and 100-150 mm wide, forming a defined edge between driveway and garden, or along the sides of paths. Can be plain concrete, formed with a rounded or profiled top, or coloured with oxide pigment.
Vulnerabilities: heaving from tree roots underneath, cracking from soil movement, chipping at the top edge from lawnmower impacts, and staining from adjacent organic matter.
Formed Concrete Mowing Strips
Flat, low-profile concrete strips (25-50 mm thick, 200-300 mm wide) laid between lawn and garden bed. Very common in Gosford, Erina, and Kincumber residential properties from the 1980s through 2000s.
Vulnerabilities: lifting from soil expansion, cracking transversely, and edges breaking away. In coastal areas, salt air affects any exposed surface.
Decorative Border Edging
Some driveways and patios have a decorative border element, a contrasting colour or texture strip around the perimeter. This is often part of a stencilled or spray-on concrete installation.
Vulnerabilities: colour fading differently from the main surface (borders are often darker and fade more noticeably), edge chipping in high-traffic areas.
Refresh Option 1: Grind and Reseal
Best for: Sound concrete edging that’s just cosmetically tired, faded colour, surface oxidation, slight staining.
Diamond grinding the top and face of the edging exposes fresh concrete, removes old degraded sealer, and provides a clean surface for resealing. A colour-matching oxide sealer or decorative concrete sealer then restores the appearance. This is particularly effective on coloured concrete kerbing where the surface has bleached out but the colour oxide below is still rich.
Cost: $15 to $25 per linear metre for professional grind and reseal. DIY potential: Medium, requires a small angle grinder with diamond cup wheel, which is manageable for a homeowner.
Refresh Option 2: Crack Repair and Recoat
Best for: Edging with minor cracking (under 3 mm) and some surface deterioration, but still structurally in place.
The process:
- Clean all surfaces thoroughly
- Fill cracks with a polyurethane or epoxy crack filler, allow to cure
- Apply a flexible concrete coating or oxide-tinted sealer over the repaired surface
This approach is particularly effective for mowing strips and low kerbing where the cracking is cosmetic rather than structural.
Important: Fill cracks with a flexible sealant rather than a rigid filler, because concrete kerbing and mowing strips experience seasonal thermal movement that will re-open rigid repairs.
Cost: $10 to $18 per linear metre for professional crack repair and recoat. DIY is very feasible for straightforward cracking.
Refresh Option 3: Full Removal and Replacement
Best for: Edging that has heaved significantly from tree roots, is broken into sections, or has soil movement that makes it non-functional (no longer retaining the garden edge, no longer providing a defined driveway border).
Replacement involves:
- Breaking out the failed edging (jackhammer or angle grinder)
- Addressing the cause (tree root management, drainage improvement, soil compaction)
- Formwork and new poured concrete edging
- Allow 28 days cure before sealing
Matching new concrete edging to an existing driveway or patio is difficult, new concrete always looks slightly different in colour. If colour matching matters, plan to coordinate the edging replacement with a general driveway reseal that blends the whole surface.
Cost: $40 to $70 per linear metre for removal and replacement.
Dealing With Tree Root Heaving
Tree roots under concrete edging are the most common cause of structural failure. The options:
- Remove the tree: Sometimes the right decision, but not always practical or desirable.
- Root barrier: When replacing edging, a root barrier (HDPE sheet installed vertically under the new edging) can deflect future root growth.
- Root pruning: Cut back invading roots before replacement. Note that aggressive root pruning can destabilise or kill the tree if done incorrectly, consult an arborist for significant trees.
- Flexible edging material: Some homeowners replace broken concrete mowing strips with rubber or metal garden edging, which accommodates root movement without cracking.
Decorative Border Options
If you’re replacing edging as part of a larger driveway or patio upgrade:
- Exposed aggregate border strip around a plain spray-on driveway creates an attractive contrast
- Colour-contrasting spray-on border, a darker or lighter tone around the perimeter of a driveway is easy to execute during a resurfacing job and adds significant visual definition
- Formed edge profiles, during a new concrete pour, a profiled form creates rounded or chamfered edges that look finished and professional
FAQs
My garden mowing strips are all cracked, is it worth repairing them or just replacing them?
For widespread cracking across many sections, replacement is usually the better value decision, the labour in patching many short sections individually approaches the cost of replacing the whole run. For isolated cracked sections (2-3 cracks in an otherwise sound strip), crack repair is cost-effective.
Can I match new concrete edging to my existing 15-year-old driveway colour?
Closely, but not perfectly. New concrete cures to a lighter colour and weathers differently than old concrete. If colour matching is important, discuss a full driveway reseal at the same time, unifying the surface under a common sealer colour blends old and new effectively.
My decorative border on my stencilled driveway has faded to a different colour than the centre, can this be fixed?
Yes, the border can be selectively recoated with a colour-matching concrete coating. This is a detail-intensive job that requires careful masking but is achievable. Alternatively, if the whole stencilled driveway is due for resurfacing, the new overlay will include the border in a cohesive colour scheme.
What’s the cheapest way to refresh the appearance of tired concrete garden edging?
Pressure washing and a fresh coat of exterior concrete paint is the cheapest approach. Results are modest but provide a clean appearance for 2-3 years. For better results that last 5+ years, grinding and resealing is a better investment.