The specific epithet honours British Antarctic explorer James Clark Ross, who visited Campbell Island in December 1840.

Bulbinella rossii is a large, dioecious, perennial lily, growing up to 1 m in height and with a basal diameter of 40 mm.

The golden yellow flowers are densely crowded, 10–14 mm in diameter, and are often flushed with orange.

Because it thrives where the ground has been disturbed, and because it is not particularly palatable to browsing animals, it is common near old human habitation sites and may form dense colonies in open herbfield and tussock grassland.

The species is listed as "At Risk - Naturally Uncommon" in the most recent (2018) assessment using New Zealand Threatened Classification for plants, because of its restricted range.