Flowers of mentzelia jonesii
are formed of five narrow, reddish-green sepals, sparsely hairy, about 0.3 inches in length, and five ovate petals, at least twice as long. Petals tips are rounded, and may have a tiny point at the center. Petals may be orange at the base. At the flower center is a group of thread-like stamens and styles, similar in length to the sepals. Flowers are subtended by green, lance-shaped bracts, with entire margins.
Stems branch a few times, generally above the middle, and the branches may bend down towards the ground. Stems are usually hairless, while the leaves have a sparse hair covering. Basal leaves are deeply pinnately lobed; those up the stem are progressively less lobed, and shorter. Basal leaves may have stalks, cauline leaves are sessile.