this plant doesn't come back each year but each flower make a pod with about 75+ seeds and when the pod opens and the seeds reseed themselves . It is easier the grow the plants in a big pot with acidic soil and well drained . when the winter comes bring them in and put in a sunny window and they will bloom all winter long and get bigger and bushier each year. the seeds need lots of room , i start mine in a 10 in pot and when the stalk turns gray i separate the plants into there own pot. In my opinion the best potting soil is the rose soil with rabbit manure added to it. All the seeds i planted in late June are now blooming . They have a very light fragrance buy itself but if you have 5 or more it gets stronger especially at night. thank you for asking