Density and diversity

By Warren and Gloria Sheather

The Northern Tablelands of NSW is a challenging area to establish gardens. Winters are usually characterised by a series heavy frosts throughout the season. This presents problems particularly if you wish to cultivate native plants as many come from milder, coastal and more temperate areas.

Density and diversity, image Warren and Gloria Sheather

Density and diversity, image Warren Sheather

Our garden is situated on a windswept, 900 metre high hill west of Armidale on the Northern Tablelands of NSW. We have succeeded in successfully cultivating a wide range of native plants by copying nature. In any given area of bushland (eg the Hawkesbury sandstone country around Sydney), there is a wide range (diversity) of native species growing close together (density).

We achieve density and diversity by planting three plants (usually tube stock) in each planting hole with holes spaced about 75 cm apart. This results in dense shrubberies where the plants shelter and protect each other. Usually we have three different plants in each hole. The type of plants used depends on the position in the garden. Near paths smaller plants are used such as correas. Away from paths taller as well as shorter plants are used. In this case eucalypts, wattles, hakeas and taller grevilleas are some of the varieties used. We cultivate plants from every Australian environment except rainforest.

Even our dense, protective shrubberies are not enough to protect many of these frost-prone, rainforest species.

There are number of spin-offs from this planting method. We have created ideal habitat for small native birds. The dense plant growth shades the ground and inhibits weeds. Also using a diversity of plants there is always something flowering in the garden.

To afford this planting method we propagate over 95% of the plants used. This cultivation method is not everyone’s ‘horticultural cup of tea’ but it has been extremely successful in our domestic landscape. 

The photo illustrates a section of dense shrubbery in our garden. The plants shown are: Grevillea hybrid, Melaleuca decussata, Calothamnus sp and Correa sp.