Winter Bronzing on Yoshino Cryptomeria

It's normal for 'Yoshino' cryptomeria to develop a bronze-purple cast in winter, especially on plants exposed to cold, drying winds. The discoloration is temporary—foliage greens up again in spring. As the tree matures, bronzing becomes less pronounced. No treatment needed; just ensure adequate watering before the ground freezes. If the bronze color bothers you, consider a more winter-green cultivar like 'Radicans'.