Sesbania punicea aka Brazilian Glory Pea

Sesbania punicea is a deciduous shrub or small tree. Common names include scarlet sesbane, rattlebox, and false poinciana. It belongs to Fabaceae, the pea family. Its native range runs from central and southern Brazil to northeastern Argentina. It grows in subtropical regions. It has spread into parts of the United States coastal plain. There, it can invade sites and displace native plants.

This fast-growing plant has an open, spreading crown. Virginia Tech gives a height of 6–8 feet [1.8–2.4 metres]. NC State reports plants reaching 15 feet [4.6 metres]. It can form dense thickets as it spreads. Slender stems stay green before turning dark reddish brown. The bark ranges from gray-brown to reddish brown. Horizontal lenticels stand out on its surface. Green leaves grow in an alternate pattern along the stems. Each pinnate leaf has 6–20 pairs of leaflets. The oblong leaflets have smooth edges and pointed tips. The whole leaf reaches about 0.5 feet [0.15 metres] long.

Flowers bloom through summer in hanging clusters. Their pea-like shape marks their place in the legume family. The blooms range from red-orange to reddish purple. Each flower has five joined petals and five joined sepals. Brown, four-winged pods follow the flowers. These reach about 0.3–0.5 feet [0.10–0.15 metres] long. Slight narrow points mark the spaces between seeds. The pods stay on the plant through winter. Wind shakes them and makes the seeds rattle. Water can carry the pods to new sites.

It prefers moist or wet soil and tolerates occasional flooding. Slightly acid soil suits it, though NC State also lists neutral soil. It grows in full sun or partial shade. NC State places it in USDA zones 8a–11b. Growers can raise it from seed. Its flowers and foliage have led to ornamental use. Yet its spread makes it a poor planting choice where invasive. NC State rates its upkeep needs as high. The same source reports no major pest or disease problems.

Flowers, leaves, and seeds contain poisonous saponic glycosides. Eating them can cause nausea, vomiting, stomach pain, and diarrhea. Severe poisoning can cause weakness, breathing failure, or death. This is not a plant to treat as food. NC State flags a risk to children. It does not report contact dermatitis.