Bonsai
Introduction:
Bonsai is an old
Chinese art of growing trees. Bonsai comprises a tree or shrub planted in a small
container for developing as a miniature plant showing the general appearance of that plant
species found in nature. It differs from a pot plant where the foliage and flowers are
important whereas for Bonsai the appearance of the plant in a miniature form is to be
maintained for many years.
Plants Suitable for
Bonsai
Although the
suitability of plants for developing as Bonsai has been tested in Japan consisting mostly
of sub-tropical and temperate plants, very little information is available on the response
to the growth of tropical trees in miniature form. Late Shri V.P.Agnigotri has developed a
technique of dwarfing trees commonly found in this country. The suitability of a tree to
develop as a Bonsai depends on various factors:
The plant should be
hardy so that it can be grown in a small container for many years with all the
manifestations of a living plants.
The trunk should
develop a natural appearance.
The branches should
grow in natural but artistic forms.
The growth of the
plant and its appearance should be harmonious with the shape of the container.
The miniature plant
showing seasonal variation in growth and flowering is a very interesting feature of
Bonsai.
Plants of low height
and strong trunk, thick at the base are good as Bonsai.
Among the tropical
trees that thrive well as miniature plants are: Adonsonta digitata, Anthocephalus cadomba,
Bombax malabaricu, Adenanthera pavonina, Brassia actinophylla, Butea frondosa, Caesalpinia
coriaria, Erythrina cristagalli, E.parcelli, Ficus religiosa, F.bengalensis, Jacaranda
mimosaefolia, Kigelia pinnata, Putranjiva roxburghii, Tabebuia chrysantha and Thespesia
populnea.
Several tall shrubs
like Adenium obesum, Brya ebenus, Fortunella japonica, Hamelia patens, Hibiscus
schizopetalous, Jatropha podagrica and Murraya exotica form very attractive dwarf plants.
Woody climbers like Combretum, Derris scandens, Hiptage madhablata, Roupellia grata and
Jasminum auriculatum can also be trained as Bonsai. Among the conifers grown in tropical
conditions, Juniperous prostrata and Pinus khasiana will form good Bonsai.
Growing the Bonsai
Plants suitable for
growing as Bonsai are planted in small containers. In tropical climate, the monsoon is the
best season for planting or transplanting. For making Bonsai, plants growing wild or
seedlings grown in the nursery for several years should be carefully uprooted, grown in
ordinary pots for a year or two and then planted in a shallow container. Plants may also
be obtained from layering of a large branch, grafting or by raising seedlings in a pot.
It is advisable to
grow the plant in the ground for a year or two which helps in developing a strong root
system and healthy branches. They are the transferred into a container after pruning the
roots and branches. The plants grown in pots may also planted directly in the container.
Containers
The containers should
be unglazed shallow pots of various sizes and shapes. They may be round, rectangular or
square, the size and depth depending on the plant to be grown. The containers should be
simple and non eye catching.
Soil
The soil for potting
should be fresh, well-drained, and on very rich in fertilizer. It should not be highly
acidic or alkaline. Clayloam or loam of different structures and clump sizes, obtained by
sieving the soil is used in potting. It should not be very sticky or sandy. Well-rotted
leaf mould is mixed with the soil.
Soil Preparation
The soil is dried in
the sun and sieved through meshes of at least three sizes. Large, medium and fine soil
obtained by sieving are kept in separate containers. At the time of planting, the larger
particles are placed at the bottom of the pot and a thin layer of medium-sized particles
is spread over it. The tree is planted and the top soil consisting of small particles
holds the plant in position and comes in close contact with roots.
Removal of tree
The soil of the plant
to be transplanted should be kept on the dryside to facilitate removal of the plant from
the pot. It may be necessary to remove thick roots and also the tips of some fibrous roots
with a pair of sharp shears. After pruning the roots, the shoots are pruned depending on
the growth habit and the desired appearance of the plant in miniature form, when the
branches are crowded in any part of the plants. In the case of unbranched seedlings
growing terminally, the main stem is cut to a height, which may form a well-shaped Bonsai.
If the branches are
small and well arranged, pruning is not needed but the terminal growth is removed to
minimise the height of the plant and to encourage the growth of auxillary branches. In
case the branches have already grown to a size too tall for a Bonsai, they are pruned to
1/2 to 1/3 the length depending on the rate of growth of the plant and its response to
pruning. Generally broadleaved plants and harder pruning than small-leaved conifers.
Planting in Container
The holes of the
container are first covered with crocks or plastic net. Then a layer of large soil
particles is placed with a thin layer of medium-sized soil above it. The tree is then
placed in the soil. Before it is finally planted, the side presenting the best view should
have been determined. The medium-sized soil is placed around the root region a
consolidated by means of a bamboo stick without pressing too hard. Then a layer of fine
soil is spread on the top, levelled and pressed gently. While planting, care should be
taken to keep the base of the trunk from where the main roots rise above the soil and to
place the plant in the middle of the container. After planting, watering should be done
with the help of a fine rose from the top of the plant.
Care of the Plant
The container is kept
on a platform in a cool and shady place for about two weeks to allow the roots to develop
and the plant to establish. It is then gradually exposed to sunlight for longer durations
beginning with the morning sun for two hours. The soil should never be allowed to dry up
completely. In summer months with high temperature and low humidity, the plants may be
placed in shade in the midday and afternoon. They also need protection from frost. The
miniature plants should be arranged in a planned fashion on a plantform or on stands of
different sizes and heights so that the collection of plants looks like a garden. Proper
spacing between the rows will facilitate watering the maintenance of the plants.
Watering
Watering is very
important for Bonsai, as they are grown in shallow containers with small amount of soil.
They should not be allowed to dry as temporary wilting of the plants adversely affects
their growth. If the roots shrivel due to shortage of moisture in the soil, the plants are
likely to die. Excessive watering often causes poor growth and waterlogging for a
considerable period may cause rotting of the roots.
Pruning and Pinching
Removal of buds from
Bonsai is an important practice. Pruning maintains the shape of the plant, stimulates
branching and helps in the utilization of energy for the growth of other parts of the
plant. The frequency and mode of pruning will depend on the growth habit rate of shoot
growth, response to pinching and subsequent growth of auxiliary shoots.
In order that the
plant may maintain an attractive appearance, pinching is not done at the same length in
all the direction. In the case of two axillary branches growing in two directions, one may
be pinched at the apical bud, while the other one is pruned up to several nodes below the
terminal bud. If the plant tends to grow fast in a particular season or continues to grow
in length throughout the year if may be necessary to pinch more than once a year. But
frequent pruning leads to the formation of thin and weak shoots, which may wither in an
unfavourable environment. Pinching or pruning should be done clean without damaging the
shoot at the cut end It should be ensured that the plants remain in a fixed position and
the soil and root are not disturbed at the time of pruning. Bonsai varies in shape and
size. Following are common types:
A single tree with
straight trunk
A tree with twisted
trunk
A tree with slanted
trunk
A tree with a large
hanging branch
A tree with two
trunks
A tree with several
trunks
Several trees grown
in a single pot
Tree grown on rocks
Arrangement of
Branches
The arrangement of
trunk and branches is also an important technique to be followed to develop an attractive
Bonsai. It is done to improve the shape and to help in the manifestation of natural
appearance of the plants. In order to maintain the space between two branches the lower
one is suspended by a strong twine or wine.
Before using wire, the
portion of the branch is wrapped with raffia where the wire is to be tied. To improve the
arrangement of the branches on the plant, wire is to be used very carefully and the
technique needs experience, skill and proper tools. Wire cutter and pincers are normally
used for the purpose. Copper wire is better than iron wire, as it is softer and can be
seen easily and does not rust.
Another very effective
method of modifying the shape of the tree or arranging the branches is to tie wire around
the trunk or branches so that they may grow in the desired direction and form.
Repotting
Bonsai needs repotting
when the soil is completely exhausted or the container is filled with roots. In general,
plants in the growing stage are repotted once a year, and a full-grown tree once every two
or three years. Containers should be used after thorough washing and drying. While
repotting, the old soil should be removed as far as possible and dead roots and ends of
fine roots pruned. Unnecessary branches are also removed to improve the appearance of the
tree. Then the Bonsai is planted firmly in the container using the similar type of soil
mentioned earlier.
Application of Manure
and Fertilizer
Fertilizer is
necessary for Bonsai as the plant thrives and grows in a small container. One kilogram of
mustard cake is diluted with six litres of water and allowed to decompose thoroughly.
After about 3-4 weeks, the water above the decomposed manure is again diluted with 5-10
times the amount of water and the dilute solution is applied to the soil leaving the base
of the trunk. Thoroughly powdered cake is lightly mixed with the topsoil slightly away
from the trunk, in two or three areas using 1-2 tablespoonful of cake in each case.
The plants should be
manured in the spring and again in the rainy season when they show vegetative growth.
During the growing season the plants can be manured once a month followed by watering.
Control of Diseases
and Pests
Diseases and pests are
common with Bonsai. Root rot is a common and serious disease caused by excess watering,
drying of soil, poor drainage, direct contact with undecomposed organic matter, etc. the
affected plant will show poor growth and decay of shoots. In the case of fungus infection
either on shoots or on root, the diseased part should be removed at the earliest
opportunity. Spraying of insecticides and fungicides should be a routine practice. |