Nature, light, water, spirit
Hindus associate the lotus blossom with creation mythology, and with the gods Vishnu, Brahma, and Lakshmi. From ancient times the lotus has been a divine symbol in Hindu tradition. It is often used as an example of divine beauty, for example Sri Krishna is often described as the 'Lotus-Eyed One'. Its unfolding petals suggest the expansion of the soul. The growth of its pure beauty from the mud of its origin holds a benign spiritual promise. Recall that both Brahma and Lakshmi, the Divinities of potence and Wealth, have the lotus symbol associated with them as their seats. (...)
The lotus flower is quoted exstensively within Puranic and Vedic literature, for example.One who performs his duty without attachment, surrendering the results unto the Supreme Lord, is unaffected by sinful action, as the lotus leaf is untouched by water. Bhagavad Gita 5.10
Borrowing from Hinduism, in Buddhist symbolism, the lotus represents purity of body, speech, and mind, floating above the muddy waters of attachment and desire. The Buddha is often depicted sitting on a giant lotus leaf or blossom.
The concept of spriritual beauty rising from dirt fits well with Andersen's – and romanticism's – ideals and philosophy. Cf. the destiny of the ugly duckling or the little mermaid, not to mention Andersen's autobiographies.
As the glorious lotus flower, torn from its roots, is carried away by the whirling river, so was the Dryad carried along, and whenever she stopped she changed into a new form; consequently, no one could follow her, recognize her, or even view her.