Lepidium bidentatum var. owaihiense is a subshrub growing to heights of 15 to 60 cm, characterized by its pubescence of simple hairs. The stems ascend to a weakly erect position and are herbaceous for most of their length, becoming less hairy (glabrate) with age. The simple leaves are arranged alternately or occasionally opposite each other, with obovate, spatulate to oblanceolate, and rarely nearly linear blades measuring 3 to 12 cm in length and 0.3 to 2.5 cm in width. The leaves have obtuse to acute apices and are thick, somewhat fleshy, and glabrate, with coarsely serrate or crenate margins, usually on the upper two-thirds. They are petiolate, without stipules. The plant’s flowers are typically bractless and arranged in one or more terminal racemes, with sparse to moderate puberulence. They are bisexual and actinomorphic, occasionally slightly irregular, and present in white, pale yellow, or greenish colors. The flowers are 2 to 3 mm long and may sometimes be absent. The calyx has four deciduous, erect, and oblong sepals, with the inner two sometimes having gibbous bases. The petals are four in number, yellow, white, or lavender, with entire to emarginate margins, and typically possess an elongated claw. It has six stamens, each with a gland at the base, with anthers that open by longitudinal slits. The superior ovary is 2 to 4-carpellate, usually 2-celled by a false septum, and bears ovules on parietal placentas, with a short or absent style and a capitate stigma. The fruit is a capsule, elongated and often referred to as a silique, divided into two cells by a thin and membranous septum, and suborbicular silicles usually measure 4 to 5.5 mm in length. The seeds are pale reddish-brown, narrowly obovoid, and compressed, becoming mucilaginous when wet, with virtually no endosperm. It is indigenous to coastal areas and low elevations, in dry, steep, and rocky slopes between 0-240 meters.