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GENERAL
Origin
:
sub-tropical,
tropical
Vigour
:
fairly fast
growing
Humidity
:
semi-humid, very
humid
Propagation :
sowing and
pricking out
Maintenance :
low
CONDITIONS
Urban climate :
vulnerable
Dessication :
vulnerable
Stagnant water :
vulnerable
Irrigation
:
medium
Salinity/ppm :
moderate (3000
ppm)
Hardiness
:
+3°C
SHAPE
Type
:
shrub, shrub
Height
:
1 m-2 m
Spread
:
1 m-2 m
Foliage
:
evergreen
FLOWER
Colour
:
yellow
Size
:
2 cm
Period
:
March - October
FRUIT
Type of fruit :
pod
Fruit size
:
12 cm
Toxicity
:
poisonous
This medium-sized shrub originates from tropical America. It grows slender twigs with com-
pound, dull-green leaves to a total height of some 2 metres with an equivalent width. The al-
ternate, evergreen foliage is compound with elliptical leaflets of 2 to 10 cm that may exhibit a
reddish venation. From autumn until spring, yellow-orange flowers emerge in terminal racemes
with up to six florets each. They resemble pea flowers measuring about 3 cm across, and attract
bees and butterflies. Seeds ripen in cylindrical, glabrous pods of 12 cm in length. Their colour
varies from olive-green and brown to almost black, and they can be used for propagation after
being soaked for 24 hours. When roasted, they can serve as substitute for coffee beans, hence the
common name Coffee Senna. Another common name, Septic Weed, indicates that it occasionally
escapes from cultivation found on disturbed ground such as waste sites or ditches along roads.
In Arriyadh, this can be excluded beyond irrigated areas, while in humid tropical countries they
compete with crops. If bruised, this plant exudes a foetid smell. Plants are poisonous, but rarely
ingested by livestock. Any soil with sufficient moisture is suitable, and the shrub benefits from
fertile ground with high nutrient levels. It thrives in full sun to produce a stunning floral display.
Under adverse conditions, Coffee Senna is short-lived and even grows annually in some regions.
With respect to its proliferating habit, this shrub is useful in low-maintenance areas. It rarely
suffers from disease.
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Senna occidentalis,
Caesalpiniaceae
Coffee Senna,
Septic Weed