Bonsai artists shape trees in containers to mirror their natural growth patterns, with style selection based on both horticultural needs and aesthetic goals. The art form traces back to penjing in China before evolving into Japanese bonsai, with styles serving as guidelines rather than rigid rules. Trees can be restyled throughout their lifetime due to artist changes or physical damage like branch loss.

Five basic styles form the foundation: formal upright (Chokan) features perfectly straight trunks tapering from base to apex, commonly seen in open areas without light competition. Informal upright (Moyogi) depicts trees shaped by elements like wind, with non-linear trunks creating asymmetrical balance. Slanting style (Shakan) shows trees tilted by wind or reaching for sunlight, developing stronger roots on one side for stability. Cascade (Kengai) and semi-cascade (Han-Kengai) styles represent trees on cliffs, with cascade trunks growing downward below the container base.

Additional styles include broom (Hokidachi) with radial crowns ideal for deciduous trees, and literati (Bunjingi) featuring tall, crooked trunks with minimal branching from competition for light. These styles help artists honor a tree's natural environment while allowing for personal creativity and interpretation in shaping miniature landscapes.