Furthermore, Liu created his own distinctive grouping of the "Four Common Ones" — the sunflower, cockscomb, canna lily and the peony — which he said were quite common in Sichuan and in which he felt the same spirit of positivity and persistence demonstrated by people at the grassroots.

At one point in the 1960s, Liu lived in a village near the Daba Mountains, where he saw many cockscombs growing around the farmhouses. With his strokes, he gave the plant a monumental feel that inspires respect. "Blooming in the fierce sunlight, cockscomb flowers remind me of the perseverance and the will to never succumb to hardship of my fellow Sichuan people," he once said.

Hong says that Liu toned down the intellectual, elite overtones of classic Chinese art, and lent it a more down-to-earth quality; the flowers in his work do not look proud or indifferent, but erupt with dynamism and vigor to touch the hearts of the public.

His reforms were his way of "practicing his teacher Pan's discipline that we should respect tradition, but not confine ourselves to the rules of painting", Hong says.

Liu Nanping, one of Liu Bojun's sons, says: "The exhibition contains the last artworks he left us and the world. They are the most beautiful melodies, which he sang with all his energy in the last moment of his life".