Daphne genkwa Sieb. & Zucc. (Thymelaeaceae) Native of N. and C. China, recorded in the provinces of Shantung, Cheking and Hubei, but especially common around Ichang growing on limestone cliffs, on boulders, on conglomerate and in piles of stones removed from cultivated fields, flowering in March and April. It is also recorded on grassy hills and plains, usually below 100 m. Flowers lilac-blue, fragrant; fruit reported to be white. Cultivated in Japan. In English gardens this beautiful species has proved difficult. It can make a shrub up to 1.5 m high, and 3 m in diameter as in one famous specimen in New York. Brickell & Matthew suggest that warmer summers than are usual in England are needed to ripen the wood, and the flowers are often spoiled by late frosts. Hardy to -20°C. There is also a white-flowered form.