Page 58 - Tạp chí bonsai cây cảnh BCI 2015Q2

Before and after photos of
nursery-grown material in
the process of being refined.
The branches are cleaned,
thinned out and wired as
necessary and the branch tips
are arranged like those in a
Japanese-style pine bonsai to
achieve well-defined branch
pads.

Fertilizing; Fertilize with organic fertilizers during kept. Repotting should not be done during the rainy
growth periods. Slow release fertilizers like Osmocote season as the sunlight is insufficient and roots tend to
should be used at potting time. Casuarinas produce get waterlogged.
their own nitrates due to its ability to fix nitrogen in Disease and pests; Casuarina is relatively strong,
a symbiotic association with the bacteria Frankia sp. resistant to disease and pests, however occasionally
so the plant does not require nitrogen. The plant re- fungus attack can cause stem and leaf wilt and even-
sponds well to fertilizers containing phosphates. Since tual death. It is quite sensitive to improper drain-
Casuarinas grow naturally along seacoasts, spraying age or when the root system is disturbed during the
the roots with salt water periodically is recommended. repotting. The major biological cause of death is the
Repotting; Repotting should be carried out just mushroom root rot that causes dying-back, but this
prior to growth periods (early spring is best) as the can be decreased in wetter condition with perfect
buds swell. Drastic root pruning is not recommended. drainage.
Only about 10% of the roots should be cut during re-
potting. Part of the old soil around the roots should be

56 | BCI | April/May/June 2015