Red grape is an attractive, high-climbing, slender, delicate vine named for the color of its branches.
Leaves alternate, simple, 2¾–4¾ inches long and broad, heart-shaped or oval in general outline; margin with 3–5 prominent lobes, with rounded, U-shaped sinuses, teeth large and irregular; upper surface dark green, glossy; lower surface much paler green. Leaf blades of flowering or fruiting branches are smaller.
Stems of young growth are slender, grooved, tips naked or not leafy, thinly covered with whitish, cottony hairs. Mature stems are bright red or purplish red, finely striped, shiny, and smooth. Tendrils are strong; red when young. Bark on old wood separates in wide, thin plates.
Flowering is in May–July. Flowers are yellowish green, minute petals 5, dropping early; male and female flowers in separate clusters on same plant; clusters 4–6 inches long, opposite a leaf on new stem growth.
Fruit matures in September–October. Fruit bluish-black berries, round, about ¼ inch thick, skin thick, pulp juicy and sweet. Seeds 1 or 2 per fruit and about ¼ inch long; they are largest of any species in proportion to the size of the berry.