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GENERAL
Origin
:
Mediterranean,
sub-tropical
Vigour
:
fairly fast
growing
Humidity
:
extremely arid,
very arid, semi-
arid, semi-humid
Propagation :
sowing and
pricking out
Maintenance :
moderate
CONDITIONS
Urban climate :
resistant
Dessication :
resistant
Stagnant water :
vulnerable
Irrigation
:
medium
Salinity/ppm :
moderate (1800
ppm)
Hardiness
:
-9°C
SHAPE
Type
:
tree, shrub
Height
:
5 m-9 m
Spread
:
5 m-9 m
Foliage
:
deciduous
FLOWER
Colour
:
bright yellow
Size
:
1 cm - 2 cm
Period
:
March - April
FRUIT
Type of fruit :
pod
Fruit size
:
9 cm - 8 cm
Native to the Sonoran and Mojave deserts of Arizona and California, Cercidium species are not
only some of the most drought-tolerant of trees, but are also outstanding flowerers, deserving to
be used much more prominently in Arriyadh. Not often planted in Saudi Arabia, C. floridum is
nearly always mistaken for the very common Parkinsonia aculeata (Jerusalem Thorn), which in
many ways is quite similar. However, with careful observation, it is noticeable that the smooth,
bright-green bark of Cercidium is different to that of Parkinsonia. C. floridum is to be found in
the central median of the King Khalid International Airport highway. This slow-growing tree
reaches a height of 9 metres with equal spread, and is deciduous in dry and cold spells. When it
loses its fine-textured foliage, the dense, green and spiny twigs give it the appearance of an ever-
green. Fragrant masses of bright-yellow, pea-shaped flowers are a wonderful sight covering the
whole tree in spring. They are followed by pods. The blue palo verde withstands great heat and
intense sun; drought-tolerant once established, deep watering on a regular basis during the grow-
ing season encourages faster growth and spectacular flower displays. It tolerates alkaline soils and
is moderately frost-tolerant. It is propagated by seed, which germinates readily once the hard seed
coat is scarified. Blue Palo verde is a beautiful, small shade tree providing stunning spring colour.
It is useful for road and footpath planting, and as an accent in gardens, courtyards and parks.
95
Cercidium floridum,
Caesalpiniaceae
Blue Palo Verde