Sow seeds on the surface of the soil and lightly press them in—do not cover them, as they need light to germinate. The ideal germination temperature is 65-75 F. To improve germination rates, cold stratify seeds by refrigerating them for 30-40 days on a moist paper towel before sowing. When transplanting outdoors, space the plants about 12 inches apart. Avoid heavy clay soils, as they retain too much moisture and can cause root rot. Terra cotta pots are ideal containers as they retain less moisture. 

Water the plants only when the soil is completely dry. Overwatering is a common mistake and can lead to root rot. Fertilize carefully, as too much nitrogen leads to leafy growth but reduces flowering. If necessary, apply a low-nitrogen fertilizer once. For bushier growth, prune young plants when they reach about 6 inches tall. After flowering, remove spent flower stems to encourage repeat blooms. In colder climates, apply mulch around the base of the plant in late fall to protect roots from freezing.