Senna mexicana var. chapmanii
 
Common Names Chapman’s Wild Sensitive Plant, Bahama Senna
 
Zones 10A–11
 
A fast-growing, evergreen perennial native to Miami-Dade County and the Florida Keys, Senna mexicana var. chapmanii thrives in pine rocklands, coastal hammocks, and sunny disturbed sites. Its showy yellow flowers and wildlife value make it a standout in butterfly gardens and restoration projects. Listed as Threatened in Florida, it supports multiple sulphur butterfly species and native bees.
 
Key Features
Growth Habit: Upright, sprawling shrub; open form
Height: Typically 2–4 ft (0.6–1.2 m); spread 3–6 ft
Leaves: Pinnately compound; leaflets linear to elliptic; dark green; pointed tips
Bark: Smooth green stems; woody base
Flowers: Bright yellow; 5 petals with red venation; bloom year-round in South Florida
Fruit: Slender brown pods; split to release seeds; ornamental and wildlife-friendly
Ecology: Larval host for Cloudless Sulphur (Phoebis sennae), Sleepy Orange (Eurema nicippe), and Orange-barred Sulphur (Phoebis philea); attracts sweat bees, leafcutter bees, and bumble bees; extrafloral nectaries attract ants that defend against caterpillars2
 
Growing Conditions
Light: Full sun to part shade
Watering: Low; drought tolerant once established
Soil: Sandy or limestone-based; well-drained; calcareous (high pH)
Temperature: Sensitive below 32°F (0°C); protect from frost
Humidity: High tolerance; thrives in coastal humidity
Propagation: Seed; remove pods to reduce volunteer seedlings
Tolerance: Salt wind tolerant; not flood tolerant
 
Landscape Use Ideal for butterfly gardens, pine rockland restorations, and sunny native beds. Use as a specimen shrub, border plant, or mass planting. Pairs well with Croton linearis, Zamia integrifolia, and Lantana depressa.