The best way to create a bird garden is to provide birds with what they need: shelter, food, water, and places to nest.
Shelter: Birds need shelter to protect them from predators and the elements. In the winter, they need protection from the snow, and during the year they seek refuge from heavy rains, winds, and predators.
Food: Plants supply birds with a large part of their diet, from seeds and fruits to providing a home for the insects that many birds feed on.
Water: Birds need water for drinking and bathing. Smaller birds tend to bathe in 1/2 inch of water while larger birds prefer a depth of 2 inches. The homeowner can build a small garden pond, buy a birdbath from a garden center, or place a large shallow dish of water in the garden.
Nesting Sites: Birds have different requirements for nesting sites. Some birds like to build their nests in evergreens (like pine or spruce), while other birds prefer deciduous trees (like oak, birch, apple, and ash) where they can make their homes either in the intersections of large branches or in cavities in the tree trunks. Shrubs that are not too dense or thinly branched often make good homes for bird nests. Plants such as rhododendrons and viburnums do not have the three-way forks in their branch structure that can support a nest. While these shrubs offer important shelter and food for birds, they do not provide a suitable nesting site.