B. nobilis grows from solitary trunks, gray to tan in color, which show ringed indentations from old leaf bases. Trunks are 30 to 45 cm in diameter, slightly bulging at the base, and free of leaf bases in all but its youngest parts. In their natural habitat they can reach above 25 meters in height but usually get no taller than 12 m in cultivation. The nearly rounded leaves are enormous in maturity, over 3 m wide, and are divided to a third its length into 20 or more stiff, once-folded segments, themselves split on the ends. The leaves are induplicate and costapalmate, producing a wedge-shaped hastula where the blade and petiole meet. Petioles are 2-3 m, slightly armed, and are covered in a white wax as well as cinnamon-colored caducous scales; the nearly-spherical leaf crown is 7.5 m wide and 6 m tall. Most cultivated Bismarckias feature silver-blue foliage although a green leaf variety exists (which is less hardy to cold). These palms are dioecious and produce pendent, interfoliar inflorescences of small brown flowers which, in female plants, mature to a brown ovoid drupe, each containing a single seed.