Light. Full sun is needed for good flowering; light shade is also tolerated.
Water. Water regularly while it settles in; once established it is fairly drought tolerant. Roots rot quickly in waterlogged soil, so plant where water drains away.
Soil and feeding. Give it well-drained soil, ideally pH 6.0–7.0, and only moderate feeding. Mulch 2–3 inches deep.
Size. Kept at about 2 ft. Dwarf butterfly bushes stay around 3–4 ft, while full-size types reach 6–12 ft, so trim to hold it small.
Pruning. Cut back hard in early spring, before new growth starts, since most butterfly bushes flower on new wood. Removing spent flowers brings new blooms and prevents unwanted seedlings.
Problems to watch. Spider mites build up on drought-stressed plants. Many cultivars are prone to rust, and nematodes are a problem in sandy soil.
Good to know. The fragrant summer and fall flowers are a natural butterfly attractor. In Florida a plant may last only a few years, so some gardeners grow it in a large container.
Sources: UF/IFAS Gardening Solutions: Butterfly Bush · Clemson Cooperative Extension HGIC: Butterfly Bush
