Perennial sweet peas (Lathyrus latifolius) are vigorous herbaceous vining plants that produce showy (unscented) flowers in late spring and continue to flower for a long time.    They are best planted near a fence, trellis, or a wall to climb up.    Since they spread by underground rhizomes, it is best to find the right spot to allow them to flourish without invading the flower bed.    Once established they will return every year and provide more stems and flowers.

Perennial sweet peas prefer moist soil and lots of sunshine.   Some support for the vines is recommended.

Seed pods form after flowering and if we pinch them off, we can encourage more blooming and less reseeding in the nearby areas.   At the end of the season, we can cut down the foliage in late fall.

These plants provide showy flower displays through the summer, but we must also be mindful that the plant is toxic, it can be invasive if not cared for, and it can be a messy hanging cluster if not maintained.