The purple passion plant, Gelsemium sempervirens, thrives in well-drained soil with rich organic matter and ample sunlight or partial shade. Water regularly, allowing the soil to dry out slightly between waterings. Prune after flowering to maintain shape and encourage new growth. Fertilize monthly during the growing season with a balanced fertilizer. Protect from frost in colder climates. Be aware that all parts of the plant are toxic, so wear gloves when handling and keep away from pets and children.