Page 48 - Ebook cây cảnh Art of Bonsai

48 Bonsai basics

Troubleshooting

Many bonsai species are accustomed to surviving in harsh
environments, and consequently they tend to be less
susceptible to pests and diseases. With good hygiene, an
understanding of how plants grow, and an awareness of

potential threats, you should be able to keep your trees
Some symptoms
happy and healthy—but sometimes things do go wrong. look alarming, but
galls like this may
just be unattractive
How to diagnose problems rather than harmful.
Close, careful observation of your trees as the ∙Monitor the soil.
seasons change is part of the enjoyment of bonsai. If it is constantly
If you know your trees when they are healthy, you wet, the roots may not be taking up enough
are more likely to spot when something is wrong. moisture and your tree will suffer.
∙Deal with problems in your garden and its trees.
∙Identify abnormal conditions. Look for unseasonal There is no point curing a spider mite problem on
color changes in foliage, brown growing tips, your juniper bonsai if it may be reinfested by the
spots appearing on leaves, or physical signs of garden juniper it sits next to.
insects such as webs—spiders are your friends, but ∙Eliminate possible environmental factors such as
spider mites are not. Dead foliage or branch loss is wind- or sunburn; too much or too little fertilizer
a sign of trouble. Poor wiring and rough handling or certain mineral elements; chemical, animal, or
damage plant tissue and may cause branches to die. human damage before considering pests and
Watch when working with or moving trees, and if diseases and how to tackle them.
branches die consider mechanical damage first. ∙Learn what your trees are susceptible to—and how to
∙Look for progression or a direct cause. If leaves turn prevent it. If a tree is partial to mildew, keep it in
crinkly and brown after a hot day and inadequate a well-ventilated and relatively dry area to reduce
watering, it is human error. If foliage discolors the likelihood of infection. Positioning in your
after spraying, then perhaps the plant is injured. garden is essential: consider cross-contamination as
∙Over- or underdeveloped foliage, well as sun, wind, and humidity, and do the best you
fruit, or roots is not normal: can in the circumstances. Understanding how and
look closer if a first when fungal spores spread will also help.
flush of leaves ∙Consider spraying with fungicides or pesticides as
is too small. a preventive measure. Start when new growth is
beginning and spray once a month with a variety
of different products through the year to protect
against a wider spectrum of pathogens.

Juniper scale can cause dieback.
Spray in early summer to eliminate
newly hatched scale nymphs.