Edging Your Beds

Edging flower beds and pathways attractively and neatly is as important as hemming a dress or framing a picture – it adds the finishing touch to a garden.

Some gardeners use edging materials as a tool to accentuate favourite plants and focal points or to display them to perfection, others use edging purely for the element of design that it contributes. There is also a very practical reason for using edging: it keeps soil and other elements separate. In the case of raised beds, it serves to contain the soil and make ongoing management of the bed easier.

In Grandma’s day, her large rose garden was edged with old bricks standing semi-upright on their narrow sides, forming a diamond pattern. The rockery was outlined with rough stones carted from a nearby koppie. The beds that held the tall dahlias, cosmos, foxgloves and other perennials were separated from the large expanse of lawn by small cement wagon wheels and chains attached to short stakes.  All these edging materials were regarded as very modern garden elements and earned Grandma accolades in garden competitions.

Edging is still (if not more) fashionable today and now there is no end to the variety of materials, both organic and man-made, that are used to enhance the shape and form of planted areas and pathways.

Life on the edge

Neatly pruned low hedges are a lovely way to mark out the edge of flowerbeds in a formal design. Westringia rosmariniformis (Victoria or Australian rosemary) and Rosmarinus officinalis ‘Tuscan Blue’ are two hardy plants that make attractive small hedges. Both are easy to grow.

Disadvantages: Keeping small hedges neatly pruned entails a fair bit of work. Also, if one of the plants dies then you are left with a bare spot that takes time to fill.

Tip: When preparing to plant a ‘living edge’ dig a trench instead of individual planting holes. This ensures that the plants will all be lined up exactly.

Framed naturally

Vegetable or herb beds edged with upright wooden poles have an especially ‘organic’ look about them. It’s a practical way of edging too, as it allows for deep mulching and keeps the pathways between the beds clear.

Advantages: Rolls of short poles connected with wire are available at most nurseries and hardware stores and they are relatively cheap. They are easy to install because they can be curved to fit any shape.

Disadvantage: Untreated wood will decay and disintegrate over time, and even treated wood eventually succumbs.

Tip: Buy poles that are longer than the final height you require for the beds so that you can install the poles by digging a narrow trench and burying the bases fairly deeply. Use a rubber mallet to tap the poles neatly into place; you don’t want to end up with a crooked edge that has individual poles leaning in all directions.

Lazy man’s edging

Long, thick, treated wooden poles, laid horizontally, are a fast and easy way to edge a focal bed. It’s simply a matter of making sure they are as level as possible. In this case, the over-sized pot in the centre of the lawn was edged in different layers consisting of a hedge of Ligustrum ibota, poles, gravel and barrel cacti, followed by another edging of poles.

Tip: Keeping the edge of a kikuyu lawn as neat as a pin and making sure the invasive runners stay away from the edging materials and out of the flowerbeds is best done on your knees with a pair of sharp sheep shears.

Sophistication meets veld

The sleek lines of a modern wooden deck can be complemented by edging it with graceful ornamental grass and pieces of slate in a bed of gravel.

Tip: Mass plant ornamental grasses, echeveria and other trendy plants in formal rows to enhance the appearance of edges made with cement and similar hard materials.

Edging as a design tool

Bricks or cobblestones can be used to great effect, both when edging and when designing ‘floor’ patterns in a garden. Here bricks were used to outline a split-level floor and partially enclose the sides of a sitting nook in a shady area beneath a tree. The two levels of the floor are filled in with pebbles.

Tip: If you are planning to use bricks, cobblestones or tiles in areas that experience a high volume of foot traffic then it is advisable to secure them in a cement base. The surface will be stronger and remain neat.

Other edging options

  • Perma Edge was used to separate the different shades of gravel in this garden. Composed of 100 cm lengths of strong but flexible steel, Perma Edge can be bent or curved to suit any landscaping design. Each length has spikes along its base so that it can be anchored in the ground and an interlocking system allows the lengths to be joined together.
  • Thick bamboo culms can be sawn into different lengths and used to make edges that evoke the feel of an oriental garden.
  • Glass bottles, such as wine or water bottles, make a quirky edging for a bed of ornamental grasses. Insert them, upside down and close together, into the soil. (Of course, by this stage, the contents should already have been consumed…)
  • Railway sleepers, the original wooden ones or the short cement look-alikes, can be used to create solid but attractive edges.
  • Pre-cast cement edging, which many gardeners may think has had its day, is still available from companies that manufacture lintels and cement garden ornaments. It is another long-lasting edging option that still has its uses.

Raising the stakes

  • Low retaining walls are useful for creating different levels within the garden; they are also used to build raised beds, typically when poor soil conditions mean it is more beneficial to garden above ground using quality topsoil from another source.
  • A low wall forms both the edge of a curving pathway and the side of a raised planting bed in which Pennisetum setaceum ‘Rubrum’ (purple African fountain grass) is thriving.  A mat of thickly planted echeveria nestles at the base of the wall.
  • While adding a strong design element to this garden, the low wall also keeps the invasive root system of a black bamboo forest in check.
  • Two different options for edging: a low wall painted bright purple and a stone-filled wire mesh gabion.
  • Design that is both on the edge and edgy: smooth mosaic work and ornamental grasses.
  • Raised edging in the form of a slate dry wall, which is easy to build and has such natural charm.

Edging benefits

  • Solid edges maintain the shapes of beds while alleviating the need for the ‘digging away’ that always seems to happen when there’s a bare space between the lawn and the beds (and which leads to an irregular, shrinking lawn surrounded by deep furrows that begin to take on a life of their own).
  • Concrete edging or cobbles laid at the correct angle can direct the flow of water towards plants. Kerbing or cobbling against the walls of a house can keep damp at bay and the walls clean.
  • Edging enhances the look of a garden, complements its design and supplies the ‘finishing touch’. 
The Gardener