Scientific: Senna artemisioides oligophylla (formerly Cassia oligophylla)
Common: outback cassia, limestone cassia, oval-leaf cassia
Family: Fabaceae (Leguminosae)
Origin: Northwestern Australia

Pronounciation: SIN-na ar-te-mi-see-OYE-deez o-li-go-FIL-la

Hardiness zones
Sunset
12-24
USDA 9-11

Landscape Use: Informal of clipped hedge, background, screen, xeric garden accent.

Form & Character: Evergreen shrub, rounded, open, create feeling of intimacy and openness.

Growth Habit: Moderate fast grower to 5 feet height with equal spread, rate of growth strongly influenced by water availability.

Foliage/texture: Medium green to gray green, somewhat pubescent, 4 leaflets/leaf, leaflets lanceolate to 1 inch in length; medium fine texture.

Flowers & fruits: Golden yellow pea flowers in late winter to early spring at same time as other Senna species, but not fragrant, dark brown bean pod fruit in late Spring to Summer are unsightly.

Seasonal color: Golden yellow in winter to early spring.

Temperature: Hardy to 18oF

Light: Full sun

Soil: Well drained

Watering: Drought tolerant

Pruning: Prune as necessary only after flowering, severe renewal pruning after flowering will rejuvenate, but like other Senna taxa make sure to leave some foliage. Frequent shearing will impact spring floral display as this plant sets flower buds in August.

Propagation: Seed, mechanical or acid scarification of seed coat is required.

Disease and pests: Root rot if soil is poorly drained

Additional comments: This is a wonderful senna that because of its relatively more coarse texture and demure habit should be more used in the smaller garden spaces of xeric Phoenix landscapes. This is a really delightful Australian shrub. Outback senna looks sparse when growing in a nursery container, but will fill in nicely once planted into the landscape.