Christmas, a northern hemisphere religious/cultural festival associated with the winter solstice and (obviously) Christian and earlier pagan religion, can seem a bit odd translated into the Australian summer.
“Ecology is Not a Dirty Word” has blogged on a few of the Australian christmas-theme-compliant plants and flowers and their ecology. Have a read of that; and here’s my add-on.
Depending on where you are, “Christmas Bush” may refer to a number of different plants. Around here it would be the shrub Bursaria spinosa, but the name “prickly Bursaria” is more common.
They are another tough escarpment dwelling plant, but you can find them all over the place. Their flowers (around Christmas, usually) have a beautiful honey scent and both these and the leaves are highly attractive to a range of native insects.
One of our native mistletoes is sometimes seen growing on them, the Harlequin Mistletoe Lysiana exocarpi. I imagine it’s attractive to birds, which generally see the colour red much better than insects.
Red white and green. There’s the colours of christmas for you! And without any reference to out-of-place snow and reindeer!