Combine their use with good mulching, irrigation and the selection of tree species suited to your soil conditions and environment, and you will get remarkable growth from tubestock plants - so it need not be expensive. Birds really appreciate having some areas of dense cover and some more open areas. By clipping some plants you can increase the density of foliage and branching to form really good cover. Prickly plants especially help give cover from cats and by tip-pruning these plants, growth becomes denser and cover is more effective. Try to establish a range of habitats, not only by having different food plants and dense and open cover, but also by using grasses and reeds, the latter combined with water.
Native grasses are particularly beautiful and can be combined with native ferns for superb displays.
Generally they need little water and maintenance, providing you control weed growth. Birdbaths or other shallow vessels of clean, cool water allow birds to drink and bathe. Beware that cats may be attracted too, so place them in a protected area. The Bird Observers Club of Australia has suggested that as many as 7.5 million birds die each year due to violation of habitat. Many birds once common in our gardens have become scarce.