If you are purely interested in attracting wildlife we'd recommend rowan, holly and lavender. Rowan's berries are irresistible to birds and were used as bait in the middle ages - hence its latin name aucuparia: avis "bird" capere "catching". The evergreen holly has the highest calorific content of any plants consumed by herbivores in the UK and its berries constitute an essential source of winter nutrients for such birds as the mistle thrush. Lavender excels at attracting pollinating insects, and can be used to create lavender oil.