There are five basic styles for bonsai trees: formal upright, informal upright, slanting, cascade, and semi-cascade. These classifications are based on the overall shape of the tree and how much the trunk slants away from an imaginary vertical axis. The numerous Japanese bonsai styles are principally variations of these five basic styles. The single trunk style is the basic design that is simplest to shape because the one trunk determines the overall composition.
The formal upright style has classic proportions and is the basis of all bonsai. It is the easiest for a beginner bonsai to develop because it requires the least experimentation, avoids the problem of selective bonsai tree pruning, bonsai trimming and should almost immediately become a displayable bonsai plant.
In this style, the form is sometimes rounded and the bonsai tree has an erect leader and horizontal branches. One of the branches is lower and extends a little farther from the trunk than the others .
Bonsai in the formal upright style look best in bonsai pottery that are oval or rectangular. Do not center the plant when placing it in the container. Plant it about a third of the distance from one end.
The informal upright bonsai style has much the same branch arrangement as the formal upright style, but the top â€” instead of being erect as in the formal upright style â€” bends slightly to the front. This bend makes the bonsai treeâ€™s branches appear to be in motion and enhances the look of informality
The informal upright style looks best in an bonsai pottery that is oval or rectangular. It should be planted, not in the center of the container, but a third of the distance form one end.
Many bonsai nurseries trees are naturally slanted. This makes them well suited to the informal upright style.
In the slanting bonsai tree style, the trunk has a more acute angle than in the previous styles. The lowest branch should spread in the direction opposite to that in which the tree slants. The top of the tree is bent slightly toward the front. Slanting trees in nature are called â€œleanersâ€ â€” trees that have been forced by the wind and gravity into non-vertical growth. The attitude of the slanting style falls between the upright and cascade styles.
In the cascade bonsai tree style, the trunk starts by growing upward from the soil, then turns downward abruptly, and reaches a point below the bottom edge of the container. For this reason, the bonsai pottery container should be placed on the edge of the table, or on a small stand.Â This bonsai style is representative of a natural tree that is growing down the face of an embankment.
Training a tree in the cascade style takes longer than in the slanting style. Choose a low-growing bonsai species instead of forcing a tree that normally grows upright into an unnatural form. The cascade bonsai tree looks best in a round or hexagonal bonsai pottery container that is higher than it is wide. The tree should be planted off-center from the cascading side.
The semi-cascade bonsai style has a trunk that is allowed to grow straight for a certain distance, and then is cascaded down at a less abrupt angle than in the cascade style. The cascading branches are thought of as the front of the tree, and the back branches are trained closer to the trunk than in the other bonsai styles. The semi-cascade bonsai should not reach below the bottom of the container, but should go below the level of the soil surface.
No matter what style you choose â€” whether single trunk specimens or groups of bonsai trees from single roots â€” everything depends on your selection of bonsai plant material, and your ability to visualize the bonsaiâ€™s final form.