Topiary is the art of clipping shrubs or trees into ornamental shapes: does this sound familiar as part of garden maintenance? Unfortunately, it is often the norm when one looks at gardens in general, especially after a maintenance visit.

While it is advisable to prune in July to reduce the impact of potential damage from hurricanes, there is a big difference in pruning methods to reduce the impact of wind and salt spray damage and the creation of geometric-shaped plantings.

The constant “clipping” of growth has no value in creating a healthy plant; it has the opposite effect in that with constant trimming you are removing the same replacement growth that, over time, creates thicker growth to the area below the pruning cut. Not only does it produce a heavier thick branch system in the lower part of the plant, it removes the new growth that is required for future pruning and growth renewal.

A perfect example of this being the oleander hedge that is literally sheared on the top and both sides, leaving thick and, on many occasions, leafless branches that no longer offer privacy and can be trespassed without difficulty. The exercise is repeated regularly, the result being an upright branch system devoid of foliage and flower.

When pruning becomes the norm on each visit by the landscape company or in the case of the “home” gardener, a flush of heavy growth becomes apparent. The question of the location of the plant becomes the subject of whether it is better to relocate the plant to another area of the garden or perhaps remove it if it is obviously too close to its neighbour.

It is important when first designing a garden that the selection of plants is considered in its relationship to its neighbour in terms of its potential growth habit and height and width. If a plant has a potential width of five feet, then each plant should be given future room to grow and planted at a minimum of six feet on centre, giving each plant room to mature naturally with the help of correct pruning procedures.

When a plant has space to grow naturally both with its branch system and root zone, it stands a better chance of staying healthy as it is not fighting for space. It receives more light and air flow, reducing the pest and disease problem created by overcrowding branches and low light.

When purchasing plants, always check the growth habit and shape as this will dictate to a fair degree the future shape and the type of pruning required to allow for good healthy growth, while allowing neighbouring plantings to grow naturally. When a plant is pruned, new growth will be initiated usually between four to six inches below the cut at a node. By pruning branches at varying heights, the “common” brush effect of new growth is eliminated, thus creating a more natural loose shape to the plant with new growth to create flowering wood throughout the growth area. Prune long whippy branches hard back and keep the “space” between branches far enough apart to allow natural growth both outwards and upwards, so the development of the plant is natural and not geometrically “produced“.

The aim of a plant bed is to appear natural with an undulating appearance when viewed from all sides. Allowing natural growth — with foundation plantings being correctly located — enables ground cover plants to in-fill quicker and act as a blanket to reduce weed growth while acting as a carpet over bare soil and reducing washout on banks.

Excess pruning is a waste of time and money that is best channelled into the initial design layout with thoughtful planning, with the end product being quality of plantings over quantity of mass or poor layout plantings. Why look at geometric forms when you can enjoy the floriferous nature and fragrances of a variety of interesting subjects!

• Malcolm D. Griffiths is a trained horticulturalist and fellow of the Chartered Institute of Horticulture in Britain. He is also past president of the Bermuda Horticultural Society, the Bermuda Orchid Society and the Bermuda Botanical Society