The leaves of white Turtlehead are narrow and measure 3-6 inches (7.5-15 cm) in length. They are sharply toothed along the edges and grow in pairs. Each pair is oriented at a 90-degree angle from the pair below. The leaves are largely stalkless or nearly so, providing a distinctive alignment pattern. They exhibit a smooth texture and a mid-green color, with prominent veins that enhance their structured appearance. The leaves are an essential characteristic for identifying this plant.

The flowers of white Turtlehead are notable for their striking appearance. They form tight clusters at the tops of stems and bloom from July to October. Each flower measures about 1-1.5 inches (2.5-3.8 cm) in length, presenting a unique two-lipped shape. The upper lip arches gracefully over the lower lip, resembling a snapdragon or turtlehead. The petals are predominantly white but may have a slight pink tinge.

The stem of white Turtlehead is green and can present itself as either round or square in cross-section. It is typically smooth in texture. The stem is medium in thickness, usually measuring around 0.1 to 0.2 inches (2.5 to 5 mm) in diameter. It features a subtle ribbed pattern along its length and branches at nodes in an opposite pattern. This branching pattern is a notable characteristic for easy identification of the stem in various environments.

The fruit of white Turtlehead is an oval-shaped seed capsule that comes to prominence from September to November. Within this capsule, one can find several seeds that are uniquely flattened with broad wings, a distinctive characteristic for identification. The seeds and their encompassing capsule are the culmination of the plant's reproductive cycle, presenting a natural package for potential dissemination. While color and specific dimensions are not provided, the textural and structural details suggest a fruit that is at once functional and adapted for dispersal, possibly by wind due to the winged seeds.