Blaue blume means “blue flower,” an important symbol within German Romanticism representing a hunger for the infinite, sexual and spiritual desire, and a surplus of emotion. The philosopher Novalis writes of the blue flower in his unfinished work Heinrich von Ofterdingen. From the introduction:
The old people were already asleep; the clock was beating its monotonous tick on the wall; the wind blustered over the rattling windows; by turns, the chamber was lighted by the sheen of the moon. The young man lay restless in his bed; and thought of the stranger and his stories. “Not the treasures is it,” said he to himself, “that have awakened in me so unspeakable a desire; far from me is all covetousness; but the Blue Flower is what I long to behold. It lies incessantly in my heart, and I can think and fancy of nothing else. Never did I feel so before: it is as if, till now, I had been dreaming, or as if sleep had carried me into another world; for in the world I used to live in, who troubled himself about flowers? Such wild passion for a Flower was never heard of there. But whence could that stranger have come? None of us ever saw such a man; yet I know not how I alone was so caught with his discourse: the rest heard the very same, yet none seems to mind it. And then that I cannot even speak of my strange condition! I feel such rapturous contentment; and only then when I have not the Flower rightly before my eyes, does so deep, heartfelt an eagerness come over me; these things no one will or can believe.