Called Benibana or Carthamus tinctorius it’s an annual that grows to 1 meter tall and has alternate hard green prickly leaves and bright thistle-like flowers. Later they turn red.
Interesting fact: the young flowers are chemically treated to wash out yellow pigment. The red pigment which remains formed an important pink dye for silk, and for make-up (for Japanese in ancient times) hence the word in Japanese for lipstick is kuchi-beni (literally lip-safflower ink). It is a crop that is grown less and less but is enjoying a revival in Yamagata Prefecture.
Safflower is cultivated for the edible oil obtained from the seed. It contains a higher percentage of essential unsaturated fatty acids and a lower percentage of saturated fatty acids than other edible vegetable seed oils. The oil, light colored and easily clarified, is used in salad and cooking oils, margarines, liqueurs, candles, and as a drying oil in paints, linoleum, varnishes, and wax cloths. Tender shoots eaten as a salad and potherb. Seeds, both edible and nutritious, are eaten roasted or fried and used in chutney. Safflower oil lowers blood cholesterol levels and is used to treat heart diseases. The flowers have been the source of yellow and red dyes, largely replaced by synthetics, but still used in rouge.
There’s also an interesting news feature about the ancient use of the dye since the Edo era at this page.
Source: Japanese Plants: Know Them & Use Them by Anne Kaneko.