Brown boronia

Boronia megastigma

Western Australian shrub with fine needle-like leaves and small bell-shaped flowers, chocolate-brown on the outside and yellow within, carrying one of the most intense fragrances of any Australian native plant.

Hardiness ratings

Brown boronia hardiness across the four zone systems
SystemRatingTemperature rangeHow to read it
USDA hardiness zone Zone 9–10 −6.7 °C to 4.4 °C Plant tolerates down to this zone
RHS hardiness rating H3 −5 °C to 1 °C Plant needs at least this level of cold tolerance
Canadian plant hardiness zone Zone 9 −1 °C and warmer Plant tolerates down to this zone
Australian (ANBG) zone Zone 4–5 0 °C to 10 °C Plant tolerates down to this zone

Growing notes

  • Endemic to southwestern Western Australia — winter-rainfall Mediterranean climate
  • Intensely fragrant — among the most powerfully fragrant Australian natives, source of boronia absolute for perfumery
  • Notoriously short-lived (3–5 years) and demanding — sharp drainage, cool root run, never wet feet; sulks in heavy soils and eastern Australian humid summers
  • Plant grafted onto Boronia clavata rootstock for longer life in difficult soils

Categories

Related plants

Cross-check Brown boronia against your zones

Reference

Brown boronia on Wikipedia