Hyacinth Bean Vine Purple Seeds offer a stunning tropical look with their rich amethyst and violet flowers, which bloom on striking purple stems throughout the summer. The flowers mature into shiny, flat 3-inch pods that hang like purple ornaments against the lush green foliage. For best results, plant seeds directly in a sunny spot with ordinary garden soil, 1 inch deep and 6 inches apart, once the weather is warm and settled in late spring, after nighttime temperatures stay above 50°F (10°C). Keep well watered and weeded. To start indoors, sow seeds in individual pots 4 weeks before the last frost, covering them 1 inch deep and keeping them warm and moist until seedlings emerge in 7 to 10 days. Once the risk of frost has passed and the weather has warmed, carefully transplant seedlings 6 to 8 inches apart, avoiding disturbing their roots. Set up a tall trellis or netting (8 to 10 feet high) to support these vigorous climbers, guiding their tendrils to twine up for a spectacular summer display.