Designing Large Scale Planters in Multiple Sections

Bespoke manufacture in Metal is the ideal choice when designing planters on a large scale.

Production constraints and logistics demand that planters over a certain size will need to be split into more manageable units.  Rather than abutting multiple smaller planters, fabricating a large planter in sections for on-site assembly is a much neater and usually more cost-effective solution.  The finished planter looks like it truly ‘belongs in the space’, enhanced by the fact that planting can be continuous and unrestricted across the whole surface area.

Sheet metal is ideally suited to this design approach in a number of ways:

• It allows us to deliver complex, site-specific geometry, to fine tolerances
• It is simple to assemble in situ
• The result is aesthetically pleasing, with very neat regularly spaced joint lines
• It is cost-effective in accommodating additional functional requirements [such as irrigation systems, lighting systems, drainage, tree anchors etc.]    
• It is cost-effective at large scale

Modern sheet metal fabrication technologies are infinitely flexible, and manufacturing tolerances are extremely precise [less than 1.0mm]. Scale economies are driven by the physical size of each fabricated element [i.e. bigger is better / cheaper], which is exactly what is needed for large scale, multi-section planters. And Metal is also free of the mould development costs that disadvantage composite materials – such as Glass-Reinforced Plastic or Fibreglass [GRP], Glass-Reinforced Cement [GRC], or Fibre-Reinforced Cement [FRC].

The above commercial issues are further explored in the following articles:

Golden Rules for Cost-Effective Bespoke Specification >>
Metal vs. GRP – Which Material Should I Specify? >>

Specification

IOTA will automatically quote for large-scale planters as sectioned units, and specifiers need not get bogged down in details of section size or construction, which will be detailed in IOTA’s drawings for approval.

Section size

Any planter with a face longer than 3000mm will need to be sectioned and it is often practical to section planters over 2400mm.  The optimal size of each section depends on the overall size of the planter, and any site or delivery constraints.  In general, the overall length of the planter is divided into equal sections of no longer than L 2400mm, ensuring that joints do not fall on or near a corner. Additional bracing is used to ensure that sections are individually stable and rigid for transport.

Assembly on site

Sectioned planters will be delivered carefully labelled up for easy identification and with all the required bolt fixings. With all metals except Corten, we recommend as ‘belt and braces’ that a line of silicone or other sealant is run along the inside of the joint to make it completely watertight.

Planting

As mentioned above, the absence of a physical division between the sections allows for a continuous planting scheme.  This is not only visually attractive, but with no physical barrier between sections, roots are less constrained and can grow and develop, laterally, as far as they please.  Maintenance can be a lot easier as a single irrigation system can often be run through the whole planted area.

In summary, a sectioned planter scheme in metal offers many advantages, and once all of the on-costs [like planting, maintenance and irrigation] are properly factored in, then it can provide excellent long-term value, as well as delivering ‘the wow factor’.