I’m an advocate of natural materials. Wood and stone underpin much of my work but I include metal in that list. You can dig it out of the ground, after all, although you have to mix a couple of metals together to make bronze and other alloys. Its look can certainly become ‘natural’. This is because it often oxidises, weathers and patinates bringing a warmth and richness to the finish. Metal is versatile. It can be fiercely modern or charmingly traditional and even rustic. You can fashion a tiny detail, such as a hinge or a water spout, or something vast like a monolithic wall. Its inherent strength and durability is fundamentally what makes it so useful.

A small north London garden by Arne Maynard
© Richard Bloom

Corten steel is structural steel. It rusts on the outside and then stops rusting with the core remaining intact. I designed large, curved sheets of it for the RHS Chelsea Flower Show in 2001 having seen the work of Richard Serra and its use in the Netherlands, particularly in architecture. At first a bright, rich, orangey colour it darkens over time but always looks incredible when combined with any green foliage and for that reason has remained fashionable and continues to crop up every year at RHS Chelsea. It’s also maintenance free and if it gets marked you can even out the finish by cleaning with cola. Being structural you can use it to make a robust staircase or a laser-cut screen, a pergola, a planter or a raised bed. It undoubtedly works best on a larger scale where it becomes a backdrop for planting, rather than when it is used as a subtle, delicate detail.

Copper is a great material for the garden but it’s soft and not very strong so more useful for smaller objects, such as light fittings. Otherwise it can be used in sheets to clad a stronger internal core, perhaps a concrete planter or a steel water chute. When brand new it’s bright and shiny but this doesn’t last long. Untreated copper will quickly oxidise becoming darker at first and then verdigris with that green patina of age, which is beautiful and unbeatable. But if you want to retain that warm, rich old-penny look that’s somewhere between shiny and green then you need to apply a wax finish once a year to seal it.

Bronze is similar in many ways and will fairly quickly settle into the dark chocolatey brown of Landseer’s lions in Trafalgar Square. The difference is that it is very strong but is also prohibitively expensive when used as anything more than a surface finish. A whole industry has now sprung up that sprays the molten metal on to a cheaper internal framework or surface. Increasingly popular in architecture it can be used as a really sophisticated finish for gates, railings and furniture and then artificially patinated and sealed. That patination process is what you want because it introduces variety and depth in the colour, which is warm and glowing and not possible with any painted finish. It tends to be more dramatic and catches the light better on larger surfaces rather than the smaller details of railings.

There are some good products developed for buildings that translate to gardens. Roof cladding systems in particular. Pre-weathered zinc and copper are artificially aged so they remain stable and don’t weather further, which makes them reliable because you know exactly how they will look in years to come and because of the intended use of the product, it won’t deteriorate. I’ve clad walls and planters in various finishes that the manufacturers intended for the sides of sky scrapers or the roofs of factories.

The most common metal finish in a garden, and probably one of the best solutions, is galvanised steel. All metal fabricators can produce it, and it’s relatively inexpensive and long lasting. Although shiny at first it soon mellows to a soft grey that combines well with timber, which time will always turn a contrasting yet complementary silver grey. This makes the two materials perfect bedfellows for gates, pergolas and so on. Galvanised steel will not draw attention to itself, which is an asset in many garden settings, unlike stainless steel, which can often clamour for attention.

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Stainless steel also has its place. The finish can be brushed rather than polished but if you garden near the coast all metals will oxidise faster in the salt-laden air, copper will verdigris rapidly and even stainless steel will rust unless it’s marine grade.

It is not just what the metal is that’s important. It’s also how it’s made and put together. Most fabricators are engineers. They deal with precise angles, flat finishes and perfect curves, which for some projects is ideal. Artistic blacksmiths on the other hand bring an entirely different skill to the party. Hammered finishes, forging of metalwork and flowing curves made by eye with a fire, a hammer and an anvil.

Andy Sturgeon is an internationally renowned landscape and garden designer. He is the winner of eight Gold medals at the RHS Chelsea Flower Show, including Best in Show in 2019. andysturgeon.com

Fine lines

A metal gate designed by Cameron Mackintosh for his home in Somerset
© Jason Ingram

Designed by Sir Cameron Mackintosh for his Somerset garden, this gate was fashioned by a local artistic blacksmith. This approach brings a special personality to a garden often elevating it to another level.