The words 'O Tannenbaum' (O Fir Free) are the beginning of a well-loved Christmas carol. This tree was named after this carol because it has the perfect shape and size of a Christmas tree.

The Tannenbaum mugo pine is a slow-growing mugo pine that eventually reaches a height of fifteen feet and a width of twelve feet after fifteen years. It has dark green needles that have a bluish cast and branches from the ground adding to its desirable form. This tree requires a sunny spot and well-drained soil but is a tough reliable plant once established, although it should be watered in hot weather when young.