Flowers of brickellia grandiflora
are somewhat unremarkable, consisting only of thin, tubular disc florets (20 to 20), pale yellow or greenish in color, which hang downwards in small clusters from the top of a lightly branched stem. Stamens and a branched style protrude beyond the end of the florets when mature. Flower heads are ringed by between 30 to 40 ovate phyllaries in several distinct rows, cream colored (sometimes becoming purplish) with green stripes; the tips are pointed and the margins ciliate.
Stems and leaves have a very fine hair covering (puberulent). All leaves are glandular; those towards the base have an opposite arrangement while those further up the stem are alternate.