EASIEST TO START OUTDOORS: Sweet peas need well-drained soil. Dig deeply and enrich with aged manure or compost. Sow seeds 1 inch deep and 3 inches apart in full sun as soon as ground can be worked in early spring. Erect a sturdy support for the short vines before planting. In mild winter areas, where the ground doesn’t freeze, plant in fall; seeds will germinate and form strong root systems, then overwinter to bloom strongly in spring. For container planting, use containers at least 12 inches in diameter filled with good quality, well-moistened potting soil. Plant seeds 1 inch deep and 3 inches apart. In summer heat, container sweet peas do best in a spot with afternoon shade. When plants have 3 or 4 sets of leaves pinch them back so just 2 sets remain. This encourages full, bushy growth.
GROWING NOTES: Sweet peas bloom best before the weather gets too hot, so if spring planting, sow as soon as ground can be worked. Be sure to protect seedlings from their most common predators: birds, slugs and snails, especially if fall planting. Mulch, keep well watered and feed plants regularly. Container grown sweet peas should be fertilized every 2 weeks for best bloom.