Chrysanthemum

"Chrysanthemums is a perennial flowering plant that is very resistant to cold and can overwinter in the open field. It has the characteristic of flower bud differentiation occurring when the day length is less than 12 hours. It has a wide variety of flower colors and flower shapes, ranging from the most commonly seen single flower type to double flower type, anemone type, pompon type like a ping-pong ball, and spider type like a thin and long spider web."
From [Naver Knowledge Encyclopedia] Chrysanthemum (Gyeonggi Provincial Agricultural Research and Extension Services, Tangka)