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.

 I could fancy I were mad, if I did not see, did not think with such perfect clearness; since that day, all is far better known to me. I have heard tell of ancient times; how animals and trees and rocks used to speak with men. This is even my feeling: as if they were on the point of breaking out, and I could see in them, what they wished to say to me. There must be many a word which I know not; did I know more, I could better comprehend these matters. Once I liked dancing; now I had rather think to the music.” –The young man lost himself, by degrees, in sweet fancies, and fell asleep. He dreamed first of immeasurable distances, and wild unknown regions. He wandered over seas with incredible speed; strange animals he saw; he lived with many varieties of men, now in war, in wild tumult, now in peaceful huts. He was taken captive and fell into the lowest wretchedness. All emotions rose to a height as yet unknown to him. He lived through an infinitely variegated life; died and came back; loved to the highest passion, and then again was forever parted from his loved one.

At length towards morning, as the dawn broke up without, his spirit also grew stiller, the images grew clearer and more permanent. It seemed to him he was walking alone in a dark wood. Only here and there did day glimmer through the green net. Ere long he came to a rocky chasm, which mounted upwards. He had to climb over many crags, which some former stream had rolled down. The higher he came, the lighter grew the wood. At last he arrived at a little meadow, which lay on the declivity of the mountain. Beyond the meadow rose a high cliff, at the foot of which he observed an opening, that seemed to be the entrance of a passage hewn in the rock. The passage led him easily on, for some time, to a great subterranean expanse, out of which from afar a bright gleam was visible. On entering, he perceived a strong beam of light, which sprang as if from a fountain to the roof of the cave, and sprayed itself into innumerable sparks, which collected below in a great basin: the beam glanced like kindled gold: not the faintest noise was to be heard, a sacred silence encircled the glorious sight. He approached the basin, which waved and quivered with infinite hues. The walls of the cave were coated with this fluid, which was not hot but cool, and on the walls threw out a faint bluish light. He dipt his hand in the basin, and wetted his lips. It was as if the breath of a spirit went through him; and he felt himself in his inmost heart strengthened and refreshed. An irresistible desire seized him to bathe; he undressed himself and stept into the basin. He felt as if a sunset cloud were floating round him; a heavenly emotion streamed over his soul; in deep pleasure innumerable thoughts strove to blend within him; new, unseen imnages arose, which also melted together, and became visible beings around him; and every wave of that lovely element pressed itself on him like a soft bosom. The flood seemed a Spirit of Beauty, which from moment to moment was taking form round the youth.

Intoxicated with rapture, and yet conscious of every impression, he floated softly down that glittering stream, which flowed out from the basin into the rocks. A sort of sweet slumber fell upon him, in which he dreamed indescribable adventures, and out of which a new light awoke him. He found himself on a soft sward at the margin of a spring, which welled out into the air, and seemed to dissipate itself there. Dark-blue rocks, with many-coloured veins, rose at some distance; the daylight which encircled him was clearer and milder than the common; the sky was black-blue, and altogether pure. But what attracted him infinitely most was a high, light-blue Flower, which stood close by the spring, touching it with its broad glittering leaves. Round it stood innumerable flowers of all colours, and the sweetest perfume filled the air. he saw nothing but the Blue Flower; and gazed on it long with nameless tenderness. At last he was for approaching, when all at once it began to move and change; the leaves grew more resplendent, and clasped themselves round the waxing stem; the Flower bent itself towards him; and the petals showed like a blue spreading ruff, in which hovered a lovely face. His sweet astonishment at this transformation was increasing, –when suddenly his mother’s voice awoke him, and he found himself in the house of his parents, which the morning sun was already gilding.