Bonsai is an ancient art that originated in China. The word bonsai is actually a combination of two words that mean tree and tray. The practice of bonsai combines both horticulture and art as bonsai gardeners grow trees and shrubs in trays. Although there are bonsai in existence that are several centuries old, with careful attention you can create a new bonsai that looks large and ancient from a new sapling.
Prune your specimen tree with a set of pruning shears. Your goal is to eliminate opposite branches and cut back longer branches. The two lowest branches should face in the opposite directions and the third should face the rear of the plant.
Wash away the roots from the root ball and cut the roots back by 1/3 to 1/2. Do not disturb the primary roots near the trunk, or the feeder roots that grow from them.
Plant the tree in a large pot to begin training the stem. When the new growth develops, wrap the tree's form with bonsai wire in a spiral up the trunk and around the main branches. Don't wrap the wire too tightly around the tree. This can cause the wire to cut into the bark and kill the tree. Carefully bend the wire into the desired shape. Rewire the tree as its size and thickness increases. Transplant the tree into a tray after it has grown this way for a year.
Cover the bottom of the bonsai tray with wire screen and with a shallow layer of pea-sized pebbles. Add a thin layer of peat moss.
Mix clay, humus and sand together in equal parts to form potting soil for your bonsai tree. Sift the soil through the wire sieves and window screen. Discard any soil that will pass through the window screen. Add the layer that is caught by the coarse sieve onto the pebbles.
Prune back new growth from your bonsai one week before transplanting the tree. Remove the tree from the large container. Loosen the soil from the roots and cut back the roots to the primary horizontal roots and their feeder roots. Work quickly so that the roots do not dry out. Leave the wire that wraps the tree in place.
Spread the roots out over the bonsai container. Pass a length of electrical wire through the holes in the bottom of the container and wrap it around the base of the plant and the roots to hold the tree in place. Add a rock or other complementary feature to the tray at this time. Add coarse soil beneath the roots to raise them to the desired level.
Add medium-grade soil to cover the roots. Work the soil into air pockets between the roots with a chopstick. Cover with a layer of moss across the top of the planting.
Saturate the soil of the tree with water from a kitchen dropper. Place the tree in a protected spot until new growth appears.