Galvanised steel edging is one of the most popular choices for garden borders, driveways, and landscaping projects. It’s strong, affordable, and designed to handle the elements, but many people still wonder how well it holds up over time.
Does galvanised edging eventually rust, or is it truly maintenance-free?
Let’s break down what galvanisation actually does, how long it lasts, and what you can do to keep your garden edging looking sharp for years to come.
Does galvanised edging rust?
Short answer: not quickly. Galvanised edging is steel coated with zinc, and that zinc layer protects the steel underneath from rusting. But it's not invincible, under certain conditions the coating can wear away or be bypassed and the underlying steel will rust.
How galvanisation protects against rust
When steel is galvanised the surface is coated with zinc. That zinc does two things:
- It forms a physical barrier that keeps oxygen and moisture away from the steel.
- If the coating is scratched or damaged, zinc provides sacrificial (cathodic) protection, it corrodes preferentially so the steel remains protected.
When galvanised edging can rust
Galvanised edging can eventually rust in these common scenarios:
- Severe or constant salt exposure: coastal areas or use where road salt is used accelerate zinc loss and corrosion.
- Acidic soils or chemicals: highly acidic or polluted environments eat away zinc faster.
- Mechanical damage: deep scratches, cuts or bending that remove the zinc and expose bare steel.
- Poor coating quality or thin galvanisation: cheaper or uneven coatings will fail sooner.
- Contact with dissimilar metals: certain metal pairings in wet conditions can set up galvanic corrosion that attacks the zinc or the steel.
Typical lifespan
There’s no single number, in sheltered garden conditions galvanised edging often lasts many decades (10+ years). In aggressive conditions (coastal, acidic ground, heavy wear) it can show corrosion much sooner. The exact lifetime depends on coating thickness, installation, environment and maintenance.
How to prevent rust and extend life
- Avoid deep scratches during installation; use rubber mallets and protective pads when bending or fixing.
- Choose a powder-coated Galvanised Steel Edging product. Alternatively, you can Paint or seal the galvanised surface (if not painted already) if you need extra protection, use primers made for galvanised metal.
- Isolate from dissimilar metals with plastic washers or barriers to reduce galvanic action.
- Improve drainage and avoid areas where water pools against the edging.
- Inspect periodically and touch up any damaged areas with zinc-rich repair paint.
When to choose alternatives
If you’re on the coast, have very acidic soil, or want a maintenance-free, decorative finish, consider stainless steel or weathering steel (Corten) depending on the look and budget.
Conclusion
Galvanised edging is an excellent, cost-effective choice for garden borders because the zinc coating protects the steel from rust for a long time. It will eventually corrode under harsh conditions or if the coating is damaged, but with proper selection and basic maintenance it remains rust-resistant for many years.