Lotus and Buddhism

Lotus is one of Buddhism symbolisms. It is a symbol of purity and enlightenment. The lotus despite growing from the mud (like greed, hatred and delusion), it is not polluted but is able to rise up and blossom. 

From the Thus I have Heard video,

There are several kinds of people in the world. The quick-witted upon hearing my teachings, know and understand them quickly, just like a lotus flower above the surface of the water that blossoms as soon as it receives the sun rays. 

Those of moderate intelligence having heard my teachings and then receiving some further explanation and training are able to know and understand within a short time, just like a lotus flower level with the surface of the water, ready to blossom the next day. 

The slow-witted having heard the teachings, receiving further explanation and training, preserving with faith are able to know and understand in the end like the lotus flower below the water which grows upwards before finally breaking through the surface and blossoming. 

The final kind of person, no matter how many times they hear the Dharma are unlikely to grasp the meaning or understand although their listening maybe a cause for realisation in a future existence. This type may be compared to a lotus down in the mud and mire, falling prey to fish and turtles, not rising up and blossoming. This being the case, I will preserve my life for the sake of spreading the Dharma. 

From Wikipedia

In Buddhist symbolism the lotus is symbolic of purity and enlightenment. It is symbolic of purity of the body, speech, and mind as while rooted in the mud, its flowers blossom on long stalks as if floating above the muddy waters of attachment and desire. It is also symbolic of detachment as drops of water easily slide off its petals.

Thus I have Heard. Lotus analogy starts from 7:50.

Lotus and Buddhism by Master Sheng Yen

The lotus flower is described in Buddhism as pure and undefiled, and as being of great benefit. It teaches us to become a person of pure wisdom, who cultivates the bodhisattva path among ordinary people, learns to be free of greed, hatred, and delusion, and only gives and contributes to our world without seeking to gain anything of this world.