Bonsai aesthetics are the aesthetic goals characterizing the Japanese tradition of growing an artistically-shaped miniature tree in a container. Many Japanese cultural characteristics, in particular the influence of Zen Buddhism and the expression of Wabi-sabi, inform the bonsai tradition in Japan. Established art forms that share some aesthetic principles with bonsai include penjing and saikei. A number of other cultures around the globe have adopted the Japanese aesthetic approach to bonsai, and, while some variations have begun to appear, most hew closely to the rules and design philosophies of the Japanese tradition.
The practice of bonsai development incorporates a number of techniques either unique to bonsai or, if used in other forms of cultivation, applied in unusual ways that are particularly suitable to the bonsai domain. These techniques include:
Leaf trimming, the selective removal of leaves (for most varieties of deciduous tree) or needles (for coniferous trees and some others) from a bonsai’s trunk and branches.
Defoliation, which can provide short-term dwarfing of foliage for certain deciduous species.
Deadwood bonsai techniques called jin and shari simulate age and maturity in a bonsai.
Wiring branches and trunks allows the bonsai designer to create the desired general form and make detailed branch and leaf placements.
Clamping using mechanical devices for shaping trunks and branches.
Grafting new growing material (typically a bud, branch, or root) into a prepared area on the trunk or under the bark of the tree.
Pruning the trunk, branches, and roots of the candidate tree.