Monocarpic or rarely perennial; stems trunk-like, to c. 1 m high and c. 4 cm diam., not forming clumps but with a few much thinner lateral branches near the base only, with prominent very broadly rhombic scars. Rosettes terminal, mostly 10-20 cm diam., rather flattened. Outer rosette lvs to c. 21 × 4 cm, 4-5 mm thick, oblanceolate or narrowly obovate-spathulate and narrowed greatly towards base, glaucous, glabrous and flat with a rounded keel on both surfaces; margins ciliolate, purple especially in upper part; apex ± mucronulate. Flowering shoots terminal, the plants probably usually dying after flowering; axis very stout, tall, erect, glabrous, with many leaflike bracts. Infl. a large, broadly pyramidal panicle, 28-37 × 25-38 cm; fls densely arranged, somewhat secund along branches. Calyx lobes 2-2.5 mm long, glabrous, broadly triangular. Petals 6-7-(8), 8-8.5 × 1.8-2.5 mm, lanceolate or triangular-lanceolate, greenish white. Stamens white, the inner whorl 4.7-5.8 mm long, the outer whorl longer. Carpels white. Scales c. 0.5 mm long, rectangular and much wider than long, ± truncate at apex. Seeds not seen.