About
Groundsel tree (Baccharis halimifolia) is a deciduous to semi-evergreen asteraceous shrub of coastal salt marshes, ditches, and wet roadsides in eastern North America and the Caribbean, with salt-tolerant leaves and fluffy white seed heads on female plants that look like cotton exploded politely. It stabilizes berms and brackish edges where less salt-honest shrubs die of chemistry. Some regions list it as invasive in disturbed wetlands—check local guidance before planting outside native range. ☀️💧 Sun and Water Requirements: Full sun; tolerates brackish soils, periodic inundation, and sandy coastal berms. Freshwater wet ditches also suit it; drought on upland sand is tolerable once established but reduces lushness. Avoid deep shade. Hardy through warm-temperate freezes; tip burn follows extreme cold snaps at range edges. ✂️ Propagation: Seeds float on wind; sow on moist sand for restoration plugs. Hardwood cuttings stuck in wet media root readily in warm weather. 🌾 Harvest / Best Use Timing: For erosion control, plant before storm season; stake small liners in surge zones. Prune female clones near patios if cottony seed offends tidy aesthetics—know sex when purchasing.
Permaculture Functions
- Wildlife Attractor: Insects use flowers; seeds feed birds; dense stems shelter small fauna in wet edges.
- Erosion Control: Roots armor ditch banks and coastal berms against scour and sheet flow.
- Border Plant: Informal screen along wet roadsides and pond margins where formality is fiction.
- Biomass: Fast soft wood chips into mulch after storm cleanup or coppice trials.
Practitioner Notes
- Dioecious drama: male plants are less fluffy; female plants snow cotton on your truck—plan parking accordingly.
- Salt spray tolerance is real; chronic road salt is still not identical chemistry—watch soil buildup inland.
- "Tree" is common-name inflation—most plants read as large shrubs unless trained.
- Storm prunings make salty mulch; use on coastal berms, not rose fantasies.
Companion Planting
- Marsh Elder — shares disturbed wet-edge ecology; stagger management to reduce allergenic pollen timing near doors
- Saltmeadow Cordgrass — low intertidal to high marsh transition structure behind shrub line
- Seaside Goldenrod — late flowers extend pollinator support in saline-influenced sun
- Regional invasiveness — outside native range it can colonize disturbed wetlands; verify local invasive lists before planting
Pest Pressure