Pruning in Bonsai

A Bonsai Plant needs to be pruned and trimmed periodically.  Pruning refers to the removal of branches.  Pruning is done so that the Bonsai retains its shape.  Pruning can also be done if you want the Bonsai to have a particular shape.

Pruning is necessary so that the tree does not waste its resources in unnecessary growth.  Pruning can be done with special tools or with any sharp scissors. 

Many trees tend to grow more at the top.  In the wild, trees compete with one another for sunlight.  Thus a tree dedicates more resource to grow taller and less resources to grow sideways.  In Bonsais this can result in a lean tree.  It avoid this, you may have to prune the top and remove the branches.  This makes the Bonsai grow sideways.

Pruning also permits light to fall on the lower branches and gives them a chance to grow.
The extent of pruning is based on factors such as the rate of growth of tree, the tree species and the desired objective. 

Maintenance Pruning in Bonsai
Maintenance Pruning refers to the pruning done to maintain the shape of the Bonsai.  As the Bonsai grows, it may lose its original shape.  Many Bonsai which are not pruned may start to resemble a small shrub.  Leaves and branches are removed to maintain the shape. Pruning should be done during the growing season which is late spring and summer.  Do not prune the tree during autumn or winter as you may not have proper perspective. 

Aesthetic Pruning in Bonsai
Aesthetic Pruning refers to the pruning done to make the bonsai take a particular shape.  This is usually done early on as the plants starts to grow into a tree.  It can also be done later.  Aesthetic pruning is done to make the plant grow in a specific direction.  Branches can be cut to make the plant grow more bushy. 
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