Since there seems to be some interest in Australian plants here at MGS I thought
Backhousia citriodora might be of interest. Commonly known as Lemon Myrtle you can believe all the good things you might find when researching this lovely small tree (or large shrub).
Lemon Myrtle is endemic to the subtropical rainforests in Queensland and is cultivated for various commercial reasons; mostly for the production of essential oil, soap and cosmetics. The leaves make an excellent substitute for lemon grass in Asian cooking. Use finely chopped & sprinkled in stir-frys or, in particular, to flavour fish. The strong lemon fragrance is refreshing when the leaves are added to pot pourri or just scattered in bowls around the house. Apart from requiring a little protection from frosts in very cold districts, Lemon Myrtle is easy to grow. A large potted specimen placed near the kitchen door will delight everyone who brushes past the scented foliage.
Here is a photo showing the fluffy creamy white flowers which are an added bonus in summer.