Mulches are a layer of organic or inorganic matter, applied to the surface of bare soil for a variety of reasons, including

  • Encouraging soil water retention, to reduce the need to frequently water plants
  • Act as a deterrent to some garden pests such as slugs and insects, and suppress weeds
  • Prevent soil erosion, particularly if the soil is light or exposed to wind
  • Protect plant roots from extreme temperatures
  • Provide nutrients and improve soil quality
  • Add a decorative touch

What are organic mulches and why do they need edging?

Organic mulches are derived from living organisms. In garden landscaping, bark or wood chippings are the most commonly used, although shredded prunings are sometimes used in municipal settings such as parks. Other examples of organic mulches are shredded newspaper, grass cuttings and hay or straw, although these are commonly used as functional mulches, rather than decorative ones.

As some organic mulches can harbour rodents and destructive or unsanitary insects such as termites and cockroaches, they shouldn’t be placed close to buildings. Landscape edging should be used to create a barrier at least six inches away from the walls of a building and the space filled with gravel or stone chippings that will deter pests and help rainwater drain away effectively.

Some organic mulches are used to create decorative paths which are soft underfoot and blend easily into natural environments, but as they are light and will float in water, they can be prone to washing away during heavy rainfall. Again, landscape edging can be used to define the edges of a path and act as a barrier to prevent the mulch from being swept into surrounding areas.

Landscape edging made from weathering steel, such as Borderline blends particularly well with organic mulches. This is untreated steel that over time develops a protective coating of oxidised metal that creates a pleasing orange-brown patina. Borderline is also available in galvanised and a powder coated brown finish. 


What are inorganic mulches and why do they need edging?

Inorganic mulches include loose aggregates such as pea gravel, slate and granite chippings, but also crumbed rubber and sheet materials such as geotextiles, soil membranes and tree mats.

As they aren’t derived from living organisms, inorganic mulches cannot be used to enrich the soil or provide nutrients. They are, however generally longer lasting and used more frequently for decorative purposes than organic mulches, and are better at weed suppression and pest deterrence.

Sheet material mulches require edging to help prevent erosion of their covering layer (they are generally laid underneath organic or inorganic mulches) and protect the edges of the sheet from lifting.

Stone-based inorganic mulches also require edging to keep them from spreading to adjacent areas such as lawns (where they could potentially cause damage to mowing machinery) and paths.

Inorganic mulches are more commonly used in urban and commercial environments for their practicality, long life and contemporary. For sleek modernity, aluminium edging such as AllEdge (designed for gardening enthusiasts) and higher-performance AluExcel will always impress.

Steel edging is also manufactured in a variety of finishes that can work well with inorganic mulches in different settings. Take Urban steel edging from Kinley Systems again as an example. While blending well with organic mulches in a natural environment, Urban edging in Corten steel can also add an industrial touch to modern garden design. Galvanised steel is another design option with excellent anti-corrosion properties, and powder-coating the steel in custom colours (matched to any RAL shade) can make the edging either blend effortlessly into its surroundings or add a pop of vibrant colour.


What’s the best edging for your mulch?

There’s not much that the Kinley team doesn’t know about landscape edging. So if you have any questions you’d like to ask about edging mulches – or anything else, for that matter – give us a call on 01580 830688 or send a message to