Schiedea helleri is an evergreen vine species that can grow at least 2 m long. It typically arches over other vegetation or occasionally sprawls on the ground, with a woody base and glabrous stems except for puberulence (finely pubescent) in the inflorescence. The stems are often swollen at the nodes, are few-branched, and are terete (cylindrical). A fibrous root system supports the plant. The leaves of Schiedea helleri are simple and opposite, with broadly deltate-ovate or deltate-cordate to lanceolate blades measuring 8–14 cm in length and 4.5–6 cm in width. The apex is acute to acuminate with a short mucro (point), and the base is cordate to truncate or sometimes broadly cuneate. The leaf surfaces are sparsely puberulent along the upper midvein, with translucent to occasionally purple hairs that are 0.2–0.4 mm long, spreading to erect. The leaves are somewhat thickened and coriaceous, usually somewhat undulate, with dark green, glossy upper surfaces with a slight purple tinge and dull green lower surfaces conspicuously infused with purple. The margins are entire, with scattered, antrorsely (upward) curved hairs, each often associated with a weak epidermal protuberance. There are three conspicuous principal veins, sometimes with an additional outer, somewhat irregular pair. The petioles are 1.3–2 cm long, strongly channeled, and puberulent. Stipules are absent. The flowers form in a terminal inflorescence with 30–164 flowers, with branches measuring 20–40 cm long, diffuse, lax, and puberulent. The bracts of the central axis are leaf-like and deltate, while those of the branches and flowers are lanceolate. The pedicels are 7–25 mm long and terete. The flowers are bisexual (perfect), with sepals measuring 1.7–3.1 mm long, ovate, green, and usually purple towards the base. The corolla (petals) is absent. There are 10 stamens with dimorphic filaments and pale yellow anthers. The superior ovary is 1-celled, with free-central ovule placentation and 3 styles. The fruit is a capsule, sub-globose to broadly ovoid, measuring 3–3.4 mm long. The seeds are 1.2–1.4 mm long, compressed, and transversely rugose, with starchy perisperm (nutritive tissue surrounding the embryo) and absent true endosperm. It is found in wet montane forests between 960–1180 meters.