The flowers, which are unscented, are about 3⁄4–1 in (19–25 mm) across with a typical structure for Faboideae, with an upper standard and lower keel, enclosed by lateral petals.

The seedpod, which is initially green, gradually turns brown, splitting open into curled segments, flinging out the seeds.

Lathyrus latifolius is a perennial herbaceous vine (climber), which can reach 6 feet or more by means of twining tendrils, but in open areas sprawls.

[5][6] It requires partial to full sun, and loam or clay-loam soil that is moist, mesic, or slightly dry.

Epicauta fabricii (Fabricius blister beetle), the caterpillars of Apantesis phyllira (Oithona tiger moth) and some herbivores feed on the leaves.