The bonsai pot size selector calculates the ideal pot length and depth from your tree's height and trunk base diameter. The classic proportions — pot length = 2/3 tree height, pot depth = trunk diameter — keep the visual balance that distinguishes refined bonsai from a potted plant. Cascade styles use a different calculation.
Tree Measurements
Apex to nebari (root crown)
At soil surface (nebari)
Style Notes
How to Size a Bonsai Pot
Pot selection is one of the most critical aesthetic decisions in bonsai development. A pot that is too large makes the tree look like a seedling; a pot too small looks uncomfortable and stressed. The 2/3 proportion rule has been refined over centuries of Japanese and Chinese bonsai practice and is the most reliable starting point.
Step 1: Measure Tree Height and Trunk
Measure total tree height from the soil surface to the apex (tip). For trees with interesting nebari (surface root flare), the trunk base diameter is measured where the trunk meets the soil — typically 1–2 cm above the soil line. Use calipers for accurate trunk measurement on small trees.
Step 2: Calculate the Classic Proportions
For upright styles: pot length = 2/3 tree height. For wider, more spreading trees, pot length = 2/3 of the widest spread instead. Pot depth should match the trunk base diameter — deeper than the trunk looks clunky, shallower risks root-binding too quickly.
Step 3: Adjust for Style
Cascade bonsai use tall, narrow pots (often round) so the cascading branch can fall below the pot rim. Semi-cascade uses a slightly wider pot than cascade. Literati (Bunjin) style uses very small, narrow pots that match the tree's refined, minimalist aesthetic.
Step 4: Consider Pot Shape
Masculine trees (angular bark, heavy trunk, deciduous species) pair well with unglazed rectangular or oval pots. Feminine trees (smooth bark, fine branching, flowering species like azalea or quince) pair well with glazed, round, or soft-edged pots. The pot material, color, and shape all contribute to the final presentation.
FAQ
How do I choose the right bonsai pot size?
The classic rule: pot length should be approximately 2/3 of the tree's height (for upright styles) or 2/3 of its widest spread. Pot depth should approximately equal the trunk base diameter. This keeps proportions aesthetically balanced without overwhelming the tree visually.
How deep should a bonsai pot be?
Pot depth for most styles should equal the trunk base diameter at the nebari (surface roots). For cascade bonsai, the pot is typically taller — pot height should be equal to or slightly greater than trunk base diameter. Shohin miniature bonsai use slightly deeper pots relative to the tree's size.
Do I need a different pot for cascade style?
Yes. Cascade (kengai) and semi-cascade (han-kengai) bonsai use tall, narrow pots — typically round or octagonal — that allow the cascading branch to fall freely below the pot rim. The pot height is usually greater than the tree's trunk base diameter.
What material is best for bonsai pots?
Unglazed clay pots are preferred by most bonsai practitioners — they breathe, dry faster than ceramic, and promote healthy root growth. Glazed pots are used for tropical species and trees shown in exhibition. Plastic training pots are excellent for development phases since the tree can grow more vigorously.
Is this tool free?
Yes, completely free with no signup required.
Does the calculator support inches and centimeters?
Yes. Toggle between imperial (inches) and metric (centimeters). Results are shown in your selected unit system.