The Chinese spinach (Amaranthus tricolor) belongs to Portulacaceae (the Purslane family). It is an annual herb that is native to tropical Asia. It was introduced to Japan in the late Edo period (about 200 years ago). The first leaves are green, but after August, the leaves on the top of the stem turn red or yellow. From summer to fall, small, inconspicuous flowers bloom at the tips of the stems and in the leaf axils. In China, it is called "莧" (xian) or "雁來紅" (yan lai hong). This is because the leaves turn red when the geese fly over.