Art of Bonsai

Bonsai is an art form that stems from ancient, oriental culture, originating in China and developed by the Japanese. In the 13th century, the Japanese collected and potted wild trees that had been dwarfed by nature. These naturally formed miniatures were some of the first bonsai.

When demand for the small trees outgrew the supply, Japanese gardeners began to train bonsai from native trees. They shaped the trees to give them the illusion of age. The art of bonsai, as developed in America, is much freer in concept and style than Japanese bonsai.

Not all plants are equally effective as bonsai. To produce a realistic illusion of a mature tree, all parts of the ideal bonsai -- trunk, branches, twigs, leaves, flowers, fruits, buds, roots -- should be in perfect scale with the size of the tree. Plants used for bonsai should have small leaves or leaves that become small under bonsai culture. Plants with overly large leaves, such as the avocado, will look out of proportion if chosen for bonsai. Sycamores also develop leaves that are too large. Certain species of both maple and oak trees usually respond well to bonsai culture and develop leaves that are in proportion. Among the plants with small leaves and needles appropriate for bonsai are spruce, pine, zelkova, and pomegranate.

Plants chosen for bonsai should have attractive bark, and the trunk must give the illusion of maturity. The trunk should have girth, but must remain in proportion to the entire tree and should taper gradually toward the top of the tree. Sometimes, one or two of the main branches must be shortened to emphasize the vertical line of the trunk and give the trunk a balanced appearance.

To give the appearance of age, the upper one-third of the root structure of a mature bonsai is often exposed. Everywhere on the tree, but mostly from the front, the branches should look balanced and appear to be floating in space; they should not appear lopsided or top heavy. The branches should not be opposite one another with their lines cutting horizontally across the trunk. The branches give the bonsai dimension and establish the tree's basic form.

A bonsai should have a harmonious arrangement of branches without unsightly gaps. Flaws can be spotted by looking down on a bonsai. Upper branches should not overshadow lower branches.

Bonsai can be classified into five basic styles: formal upright, informal upright, slanting, cascade, and semicascade. These classifications are based on the overall shape of the tree and how much the trunk slants away from an imaginary vertical axis.

Illustrations of bonsai styles.

 

Bonsai Plant Guide

Trees and shrubs are suitable for traditional bonsai. Specialty nurseries often have a wide selection of dwarf and semidwarf varieties of many species. Dwarf plants, however, do not always convey the same impression as their full size counterparts because their growth habits are quite different. Some trees and shrubs that work well as bonsai are azalea, beech, boxwood, ginkgo, maple, oak, pine, wisteria, and zelkova.

AZALEA:
Hiryu, Rhododendron obtusum
Indica azalea, Rhododendron indicum
Kurume, Rhododendron obtusum

BEECH:
American, Fagus grandifolia
European, Fagus sylvatica

BIRCH:
White, Betula papyrifera or B. pendula

BOXWOOD:
Buxus species

FIRETHORN:
Pyracantha species

GINKGO:
Ginkgo biloba

HAWTHORN:
English, Crataegus laevigata
Washington, Crataegus phaenopyrum

HEATHER:
Scotch Heather, Calluna vulgaris

IVY:
English Ivy, Hedera helix and cultivars

MAPLE:
Amur, Acer ginnala
edge, Acer campestre
Trident, Acer buergeranum

OAK:
English, Quercus robur
Pin, Quercus palustris
Scarlet, Quercus coccinea
White, Quercus alba

PINE:
Bristlecone, Pinus aristata
Japanese white, Pinus parviflora
Japanese black, Pinus thunbergiana
Mugo, Pinus Mugo
Swiss stone, Pinus cembra
White, Pinus strobus

WISTERIA:
Japanese, Wisteria floribunda

YEW:
Taxus species and cultivars

ZELKOVA:
Japanese Zelkova, Zelkova serrata

American gardeners have taken bonsai concepts and applied them to house plants. By combining traditional procedures for handling house plants with bonsai concepts of design, growers have created different bonsai styles. The following woody plants (native to the tropics and subtropics of the world) have been grown as indoor bonsai. These plants can be obtained from either local or specialized nurseries.

ACACIA:
Acacia baileyana

ARALIA:
Balfour, Polyscias balfouriana
Polyscias fruticosa
Geranium-leaf, Polyscias guilfoylei

CAMELLIA:
Common, Camellia japonica
Sasanqua, Camellia sasanqua

CITRUS:
Citrus species (Calamondin, kumquat, lemon, lime, orange and tangerine)

CHERRY:
Surinam, Eugenia uniflora

CYPRESS:
Arizona, Cupressus arizonica
Monterey, Cupressus macrocarpa

FIG:
Mistletoe, Ficus diversifolia

HERB:
Elfin, Cuphea hypssopifolia

HIBISCUS:
Chinese Hibiscus, Hibiscus rosa-sinensis Cooperi

HOLLY:
Miniature, Malpighia coccigera

JACARANDA:
Jacaranda acutifolia

JADE:
Crassula species

JASMINE:
Jasminum parkeri
Orange, Murraea paniculata
Confederate Star, Trachelospermum jasminoides

LAUREL:
Indian, Ficus retusa

MYRTLE:
Classic, Myrtus communis

OAK:
Cork, Quercus suber
Silk, Grevillea robusta

ORCHID TREE:
Bauhinia variegata

OLIVE:
Common, Olea euopeaea

PEPPER TREE:
California, Schinus molle

PLUM:
Natal, Carissa grandiflora

POINCIANA:
Royal, Delonix regia

POMEGRANATE:
Dwarf, Punica granatum 'Nana'

POPINAC:
White, Leucaena glauca

POWDERPUFF TREE:
Calliandra surinamensis

 

Creating Your Own Bonsai

Plant Selection

It is safest to begin with common plants that do well in your area. Be sure that the plants you consider meet the requirements for good bonsai. Some old favorites for bonsai specimens are Sargent juniper (Juniperus chinensis 'Sargentii'), Japanese black pine (Pinus thunbergiana), Japanese wisteria (Wisteria floribunda), Chinese wisteria (Wisteria sinensis), Japanese flowering cherry (Prunus yedoensis), and Japanese or sawleaf zelkova (Zelkova serrata). Nursery stock can be a very good selection since the plant's roots have already become accustomed to cramped conditions. Look for well-rooted specimens with good branches.

Plants for bonsai can be collected from the wild, but it is a slow method and there are many unknown factors. It is difficult to tell the age of a plant found in the wild and since they must be collected while dormant, it is also difficult to be sure that the specimen is healthy. Take all the equipment needed to keep the plant in good condition after digging. This includes plastic bags to wrap the root ball, moss to pack around the roots, and water to keep the specimen moist if it cannot be replanted soon after digging. Don't forget the crowbar; roots are sometimes wrapped securely around rocks.

Be sure to have permission before digging plants on property other than your own, and don't forget to check the endangered species list for protected plants before you begin. It is not legal to take plants from national parks and other conserved areas.

After the plant is selected, dug, and brought home, plant it in a protected area in your garden. Water the plant and feed it sparingly. After one year, it is ready to be placed in a container. A light pruning of the branches can take place at potting time, but training should not begin for another year.

It is possible to propagate your own bonsai. It is a slow method, but it has the advantage of letting you shape the plant from the very beginning. Plant seedlings in the ground outside so that the trunks will develop rapidly. They may need to stay outdoors for two to five years. Each spring, dig up the plant and prune its roots as you would if it were potted.

Bonsai can also be started from cuttings. Make cuttings in late spring before the buds open. Some plants that propagate easily from cuttings are olive, willow, cotoneaster, firethorn, azalea, and boxwood. Plants can also be propagated by layering and grafting, but these methods are not recommended for the beginner.

Bonsai Containers

Since roots must be pruned on plants for bonsai, the initial containers are different from the traditional containers used later in the plant's development. The beginning containers are called training pots. Just about anything will do that will hold the heavy roots, but it is a good idea to choose something similar to the sort of pot the plant will be placed in once the roots are small and fibrous. Cascading plants should be trained in deep pots, while tall specimens that will end up in shallow pots need to begin in fairly shallow containers. Make sure that the drain holes in all training pots are at least one half inch in diameter.

Traditional bonsai pots, available from large nurseries and some import stores, are round, oval, square, rectangular, and hexagonal. Cascade and semicascade styles of bonsai look good in round or rectangular pots. Place the plant in the center of the pot with the branches sweeping over the sides. Upright trees should be placed off center (about one third the distance from the edge) in rectangular or oval pots.

Shaping the Bonsai

Before deciding on the shape of your bonsai, study the tree carefully and take into account the natural form of the species. Observe the way mature trees of the same kind grow in their natural setting to achieve an impression of age and reality. Decide on the final shape and size of your bonsai before starting. Make a rough sketch of what you wish to create, and use it as a guide.

Once you have decided the general shape that you want the bonsai to achieve, you can use the three basic operations that will accomplish that shape. These are pruning, nipping, and wiring. A great deal of pruning is often necessary if starting with a nursery plant. Only excess foliage and undesirable limbs should be removed. Remember, make all cuts above a bud, a side branch, or a main fork of the tree. Remove all buds except those on the outside of the trunk to force growth outward and upward. Leave stubs flush with the stems. Avoid cutting back so far that the main branches are weakened.

Do not shear bonsai as you would a hedge; the objective is to make the plant look like a replica of a mature tree. Keep branches growing toward open space and away from each other. Do not prune too zealously; plants must have sufficient leaves for photosynthesis.

Heavy pruning usually only takes place once in the life of the bonsai. Once the basic form is established, shaping is done by nipping or pinching back. This procedure controls new growth. Nipping is done to shape the plant and to develop luxurious foliage. Nip off tiny spurs that appear on the trunk before they are large enough to leave scars when removed.

Roots must also be trimmed. Try to keep all fibrous roots and maintain a balance of one branch for one root if at all possible. Remove any roots that were damaged in digging. Leave surface roots intact. Prune the roots with sharp, sloping cuts to avoid damaging them.

When the plant has been pruned to your satisfaction, it can then be wired. This technique is unique to the art. Copper wire is usually used as it is flexible. Number 8 wire is the heaviest that should be used and usually only on the trunk. Use wire as light as number 16 for thin branches. Wire evergreen trees only during their dormant period and deciduous trees during their growing season.

To make the branches flexible before wiring, do not water the plant the day before you wire it. Begin at the bottom of the tree when wiring and shaping, and work upward. Anchor the end of the wire at the base of the tree by pushing it into the soil. Use foam pads under the wire to protect the branches. Keep turns around the branches or trunk about one quarter inch apart, and spiral upward at a 45 degree angle. Do not wire too tightly. If a branch should snap, the ends can be rejoined if not completely broken. Wind some garden tape around the break. If a branch snaps off, prune it back at the first side branch. Wire should not be kept on the plant longer than one year. When removing wire, start at the end of the branch and work back carefully.

Seasonal Care

Bonsai from forest trees must live outdoors except for short periods of time when they may be brought inside for viewing. These indoor periods should only be for two or three hours and should not occur at all in summer unless the interior is well ventilated.

In the summer, bonsai need cool nights, sunny days, and mist or rain almost daily. If your climate does not offer these conditions naturally, you must supply them. Avoid any extremes in temperature, light, rain, and wind. Water the entire plant daily, but do not let them become water logged. Placing bonsai on a slatted stand in the garden is a good way to keep drainage conditions optimum. Bonsai should receive three to five hours of direct sunlight a day, but the site should be shaded in the afternoon if possible.

Apply fertilizer only before and during active growth. A houseplant fertilizer diluted from one quarter to one half strength will suffice.

In the fall, bonsai must be prepared for the winter. Slow the growth of the plants by watering less frequently and discontinuing fertilizer application. Do not prune or cut any branches after mid-August.

Winter's low temperatures and drying winds can easily kill bonsai. If the winter temperature drops below 28F, bonsai must be protected by a greenhouse, pit, or coldframe. However, do not overprotect the plants; they must be kept cool to stay dormant. Don't forget to water them while inside the coldframe. Winter watering may be only necessary every other day. More bonsai are killed by overwatering than by desiccation.

In the spring, start new bonsai, prune the old ones, and continue training measures. The remaining part of the growing season is used for the plants' adjustments to these practices.

Displaying Bonsai

Remember that simplicity is very important in Japanese aesthetics and bonsai should be displayed in an uncluttered environment where the details of the plant can be appreciated. This is, after all, a wonder of nature -- trees and shrubs made miniature. Gravel beds in the garden are good backgrounds for bonsai outdoors, and a simple stand or table before a blank wall makes an appropriate setting indoors.