This mustard is a plant very similar in appearance to black mustard, but is generally shorter. It forms a broad basal rosette of lobed leaves that lie flat on the ground, and holds its leaves for the duration of flowering. Its stem and foliage have soft white hairs. The flowers, in spring and summer, have 4 yellow petals, a little more than half a cm and form very elongated clusters as the lower ones fruit. The fruit is elongated, 8-16 mm, thin, straight or twisted on the stem.