Wattle is the popular name for about a thousand species of acacia blooming all over Australia. Green and gold (the bright yellow blossoms of the wattle and its dark green leaves) are the official colors of Oz. The Golden Wattle is the national flower. Would you believe Australia commemorates a National Wattle Day? It's on the 1st of September. On that month the green landscape is splashed with countless clusters of pastel-yellow, ball-shaped flowers.