Since peppergrass is an annual, or winter annual, it is one of the first weeds to start growing actively in the spring. It thrives in turf, open fields and waste areas. Leaves are bright green, with toothed margins and blunt or rounded tips. Each leaf has a long stem that unites at the base to form a strong rosette. As warm weather approaches, peppergrass sends up a main stem that branches out at the top. Rosette leaves gradually disappear and are replaced by arrow-shaped leaves that clasp the stems of branching parts. Peppergrass has a typical "mustard" flower, with four white petals. As the flowers mature, spoon-shaped seedpods form. These seedpods have a strong "peppery" taste and give this member of the mustard family its name.