A carved bottle gourd is a work of art made of a bottle gourd carved with calligraphy works or paintings.It is said that carved bottle gourds first caught on in and around Gansu.
Originally, people just made some casual carvings on the gourd, creating some simple patterns like flowers, plants, worms, fish etc for ornament. After repeated experiments and research carried out by artisans of later generations, the carving techniques were steadily improved and the gourd carving gradually became an art in its own right.
Some artisans even created some unique color paintings on gourds by imitating the styles of master artists like Wu Changshuo, Ren Bonian, Xu Beihong and Qi Baishi etc.
Source:
http://traditions.cultural-china.com/en/16Traditions1763.html