Are metal planters bad for plants?

Not when they are detailed properly. Problems come from thin, unlined, undrained containers. A liner, a ventilated cavity, real drainage and adequate soil volume keep root conditions stable through a London summer.

Do metal planters get too hot?

Bare metal in direct sun heats the soil at the edges. We control it with liners, an air gap between skin and soil, matte or lighter finishes on south and west elevations, and deeper sections where heat load is highest.

Corten or powder-coated steel?

Corten if you want a weathered, changing surface that never needs recoating. Powder-coated steel or aluminium if you need a specific RAL, a consistent look from day one, or a lighter unit for podium loading.

Do bespoke planters need lining?

Almost always. Lining protects the coating from constant moisture, buffers temperature and lets us keep the visible metal thin and crisp rather than over-specified.

How much weight can a podium terrace take?

That is set by the structural engineer, and we design to it — switching to aluminium, reducing wall thickness, or splitting soil volume across more units to spread the load.

Can seating and lighting be built in?

Yes. Hardwood seat tops, cable routes and irrigation are designed into the fabrication rather than added later, so no brackets, pipes or fixings are on show.

Guide

Designing a custom metal planter

Depth, material, lining, drainage, weight and heat — the decisions that separate a planter that looks right on day one from one that still works in ten years.

Discuss a scheme Try the designer

How the process works

Brief and drawings

We start from architectural or landscape drawings, a sketch, or a photograph and a description. What matters at this stage is where the planters sit, what has to grow in them, and what they have to do besides hold soil — divide space, retain a level, carry seating, screen plant.

Size and soil volume

Planting drives depth, not the other way around. Grasses, herbs and perennials work at 300-400mm. Shrubs and hedging want 500-600mm. Multi-stem and small trees need 800mm to a metre. Deeper units also buffer summer heat and cut watering frequency at roof level.

Material and finish

Corten weathering steel for a warm, self-finishing patina that needs no recoating. Powder-coated mild steel for an exact RAL with maximum rigidity. Marine-grade aluminium where podium loading is tight or the site is coastal. Stainless where a brushed, architectural face is wanted.

Liner, drainage and irrigation

A liner separates soil from the metal skin, protects the coating and evens out root temperature. Below it sits a drainage layer and base outlets, spigotted into terrace drainage where the build-up requires it. Irrigation feeds are routed inside the fabrication so nothing is visible.

Joints, movement and access

Panels run to three metres in a single piece; longer runs use flush parallel or flanged return joints designed to absorb expansion. Everything is sized to the actual route in — goods lift, stair core, hoist window — and delivered in sections that fit it.

Fabrication and installation

Shop drawings go out for sign-off, then fabrication runs six to eight weeks. Our own specialist installers fit the scheme, level and fix it, and hand over with RAMS and a ten-year structural warranty. Supply-only is available where the main contractor prefers to fix.

Design questions we get asked

Are metal planters bad for plants?: Not when they are detailed properly. Problems come from thin, unlined, undrained containers. A liner, a ventilated cavity, real drainage and adequate soil volume keep root conditions stable through a London summer.
Do metal planters get too hot?: Bare metal in direct sun heats the soil at the edges. We control it with liners, an air gap between skin and soil, matte or lighter finishes on south and west elevations, and deeper sections where heat load is highest.
Corten or powder-coated steel?: Corten if you want a weathered, changing surface that never needs recoating. Powder-coated steel or aluminium if you need a specific RAL, a consistent look from day one, or a lighter unit for podium loading.
Do bespoke planters need lining?: Almost always. Lining protects the coating from constant moisture, buffers temperature and lets us keep the visible metal thin and crisp rather than over-specified.
How much weight can a podium terrace take?: That is set by the structural engineer, and we design to it — switching to aluminium, reducing wall thickness, or splitting soil volume across more units to spread the load.
Can seating and lighting be built in?: Yes. Hardwood seat tops, cable routes and irrigation are designed into the fabrication rather than added later, so no brackets, pipes or fixings are on show.

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