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Many believe that bonsai is a plant that is born with those peculiar characteristics that
represent them, just as its small size identifies it.
"Bonsai" is a Japanese word that means pot.
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This tree should be any type of plant except fruit, after these reach the desired size, this being a small size, you should use cultivation techniques such as pruning, root reduction, pots, defoliation and grafts to obtain small mature trees that mimic the shape and style of full-sized trees.
This is the technique used to obtain Bonsai. The plant to be used must be of thick trunks and the Bonsai can last up to more than 100 years of life.
Source: https://en.wikipedia.org/wiki/Bonsai