Planting & Care
Soil & Water: Perennial sweet peas will thrive in a spot with well-drained soil, so dig deeply and enrich with aged manure or compost.
Planting & Growing: Sow seeds 1" deep and 3" apart in full sun as soon as the ground can be worked in early spring. In mild winter climates, where the ground doesn't freeze, plant in the fall; seeds will germinate and form strong root systems, then overwinter to bloom strong in the spring. When seedlings are 2" tall, be sure to thin them to 12" apart to allow plants room to mature.
Young plants are easy to train up a trellis, fence, or wall, but you can also let them grow as a vigorous spreading perennial ground cover to hide neglected and bare areas. If training vines up, erect sturdy permanent support(s) for these strong growers at planting time.
Be sure to protect young seedlings from their most common predators: birds, slugs, and snails, especially if fall planting. If given good drainage, established perennial sweet peas are reliable and trouble-free and can spread quickly. To keep flowers coming, mulch, keep well-watered and remove spent blooms. In early fall, vines will begin to yellow, die back and go dormant. Cut the dead foliage to the ground. Vines will re-sprout the following spring.