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GENERAL
Origin
:
Mediterranean,
sub-tropical,
tropical
Vigour
:
fast growing
Humidity
:
semi-arid, semi-
humid, very
humid
Propagation :
sowing and
pricking out,
cuttings
Maintenance :
moderate
CONDITIONS
Urban climate :
resistant
Dessication :
resistant
Stagnant water :
vulnerable
Irrigation
:
low
Salinity/ppm :
very high (9000
ppm)
Hardiness
:
-6°C
SHAPE
Type
:
tree, shrub
Height
:
5 m-10 m
Spread
:
5 m-10 m
Foliage
:
semi-evergreen
FLOWER
Colour
:
pale yellow, deep
orange
Size
:
1 cm - 2 cm
Period
:
April - May
Smell
:
scented,
moderate, flower,
sweet
FRUIT
Type of fruit :
pod
Fruit size
:
5 cm - 8 cm
Toxicity
:
inedible
Known as both the Mexican Palo Verde and the Jerusalem Thorn, this small, fast-growing tree is
native to the southwestern United States and Mexico. It was one of the first ornamental trees to
be introduced into Saudi Arabia. A rounded, graceful tree, usually with a multi-stemmed, green
trunk, drooping branches and slender twigs, it grows up to 8 metres high and 5 metres wide. The
foliage is short-lived under desert conditions, but when the trees become leafless, the petioles of
the leaves remain like silky needles. They are bordered by two rows of 25–30 tiny oval leaflets;
during drought, the tree becomes deciduous. The branches have sharp spines 7–12 mm long.
Sporadically blooming, loose clusters of fragrant, golden-yellow flowers with an orange-reddish
coloured throat, make a striking display in spring and are followed by slender bean pods up to
15 cm long. P. aculeata prefers well-drained, sandy and alkaline, alluvial soils. In full sun, it will
need watering until it becomes established. It is a very hardy tree, and tolerant of frost, wind,
salinity and drought. Propagation is by seed. It is prone to attacks by red spider mites and mea-
lybugs. Some countries have registered invasion problems: it is now a serious, widespread weed
in Australia. Extremely attractive for landscape design, its graceful form has a residential scale
and provides filtered shade: it is also suitable as a street tree and for screening. Maintenance is
moderate: leaf litter will require removal. Pruning is necessary to create the desired shape.
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Parkinsonia aculeata,
Caesalpiniaceae
Jerusalem Thorn,
Mexican Palo Verde