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GENERAL
Origin
:
sub-tropical,
tropical
Vigour
:
normal growth
rate, fairly fast
growing
Humidity
:
semi-humid, very
humid, extremely
humid
Propagation :
sowing and
pricking out,
division
Maintenance :
high
CONDITIONS
Urban climate :
vulnerable
Dessication :
vulnerable
Stagnant water :
resistant
Salinity/ppm :
moderate (1200
ppm)
Hardiness
:
+3°C
SHAPE
Type
:
perennial
Height
:
1 m-2 m
Spread
:
0.8 m-1.8 m
Foliage
:
evergreen
FLOWER
Colour
:
purple, violet,
lilac
Size
:
20 cm
Period
:
June - September
FRUIT
Type of fruit :
capsule
Fruit size
:
2 cm
Native to tropical America, the Water Canna or Alligator Flag is a perennial, aquatic plant for
shallow water or the margins of ponds and lakes. An emergent, broad-leaved plant with rosettes
of leaves on narrow stems, T. dealbata can reach a height of 2 metres. The large, long-petioled lea-
ves, as wide as 45 cm, are alternate and sheathed with broad, lance-shaped, and veined leaf blades.
The bold, dramatic foliage is reminiscent of Bird of Paradise leaves. The lavender-purple flowers
are gracefully borne on open, bracteate, dangling clusters on very long, thin stems throughout
the summer. All parts of the plant are covered with a white, powdery coating. A further species,
Thalia geniculata, is slightly smaller, and has characteristic red stems at the base. The Water Can-
na is best in full sun; in Arriyadh, a position in partial shade is better. Plants are not frost-hardy,
so that the plant will die back in very cold weather, and re-emerge in the spring. Propagation is
by seed or root division. Pests include aphids. A robust, tropical plant, its natural habitats are
lakes, swamps, and rivers. T. dealbata is most commonly cultivated for large ponds or the edges
of lakes. It will also look well in a large water jar. Maintenance and fertilising are necessary to
keep the plant in good condition.
300
Thalia dealbata,
Marantaceae
Alligator Flag,
Water Canna