Missouri bladderpod is a non-woody, annual plant that produces numerous slender stems from its base. Leaves are less than an inch long and taper toward the stems. Both the leaves and the stems have a dense covering of fine hairs, which gives the plant a silvery-gray appearance. Blooms April-May. Flowers are typical mustard flowers, with four petals and four sepals. The petals are yellow.
Similar species: One other Physaria species, spreading bladderpod (Physaria gracilis), occurs in Missouri. Unlike Missouri bladderpod, spreading bladderpod does not have a silvery-gray appearance, and it does not occur within the range of Missouri bladderpod.