Description
Form: A subshrub with a semi-woody base and herbaceous stems.
Lifespan: Seven years or more.
Leaf retention: Deciduous.
Growth rate: Moderate.
Mature Size: 3-6' high and wide.
Flowers: Five oval shaped, vivid yellow petals, and two enlarged, curved, lower
stamens. The petals open wide in the morning and partially close by dusk to form a ball.
No nectar is produced.
Bloom: Repeatedly, throughout summer, usually after the start of summer rains, or
with irrigation.
Fruit: Slender, arced, cylindrical pods, 6" long or more, containing dark brown
pellet-like seeds in a single row. The pods remain after the leaves have dropped in the fall.
Leaves: Dark green, lance-shaped, medium-sized, hairless leaflets. In dry soil, the
leaflets tend to rotate their petioles (stems) so their surface is nearly vertical to the
ground and sun exposure is reduced. The petioles, when rotated, can also bend so the leaflet
is nearly parallel to the stalk. The leaves of individual plants vary with respect to their
aroma. Some have a distasteful smell, others none at all.
Stems: No thorns.
Roots: Nitrogen-fixing*, with a taproot.
Wildlife: Attracts several species of sulphur butterflies, small ants, and lizards
searching for ants. Female sulphur butterflies investigate this plant as a potential
caterpillar food plant, and seem attracted to the aroma given off by the leaves. However,
the eggs may be eaten by ants, or young caterpillars eaten by lizards, because late-stage
caterpillars are rarely seen. This plant may be pollinated by small ants.
Harvester ants are known to cut off the leaves of this plant when it is near to their nest
and is watered during a drought.
Toxic / Danger: There are non-specific reports of this plant being toxic to animals
which eat the leaves, in Africa, where it was introduced.
Origin: Arizona, New Mexico, and tropical and subtropical Americas.
Cultivation and Uses
USDA hardiness zones: 8-9. This wildflower dies to the ground in winter, leaving dry
brown stalks and persistent seed pods. It normally reappears mid to late spring but can be
induced to leaf out early, with regular water, starting late winter.
Heat tolerant: Yes.
Drought tolerant: Yes.
Sun: Full sun to part shade.
Water once established: Monthly. Tolerates frequent watering.
Soil: Well drained, pH 6.6-7.8 (neutral to slightly alkaline). *Do not use a nitrogen
fertilizer.
Prune: In winter, cut to the ground, except keep one short central stalk to mark the
location of its roots.
Litter: Low.
Propagation: Seed.
Uses: Ornamental, xeric garden.
Comments
This plant is a member of the Legume family (Fabaceae) and a very showy desert plant.
Cassia leptocarpa is a synonym.
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like to share? Email info@GardenOracle.com. All contributions are welcome and appreciated.
Flower mid morning
Flowers mid to late afternoon
Flowers at dusk
Leaflets with insufficient water
Slimpod Senna with sufficient water