This is a centuries-old method of trees dwarfing developed by the Chinese, that is fast becoming a popular hobby in the Western world. In short, it permits you to grow in a flower bowl.
Bonsai isn’t a difficult art. What it requires even more than skill is patience, since fully mature specimen may take ten years longer to produce.
Some plants are especially well adapted to bonsai dwarfing. Among these are junipers, Japanese maple, cypress, Mugho pine, and cryptomeria. In general, evergreens need feeding, pruning and training, but deciduous varieties are sturdier and take shape faster. Deciduous kinds also show the change of seasons; their leaves turn color in the fall and artistically trained, their bare winter form is as lovely as when they are full leaved in the summer. (One caution: use small-leaved types because the foliage is not reduced in proportion to the trunk.)
In any case, whether you choose to grow a biblical cedar-of-Lebanon, a colorful fire thorn shrub or anything from an elm or pomegranate to a yew or even a giant sequoia (scale: 1 inch to 25 feet), the method is the same.
You can start with cuttings or by layering but experienced growers usually recommend seeds. You may be able to get very tiny seedlings from some nurseries, or dig them up while on a tramp through the woods. Sandy loam is best for starting seeds. Keep them outdoors if possible, sheltered from hot sun and wind.
Before potting, gently peel the dirt from the roots—the Chinese use chopsticks for this—and cut back the taproot about one-third with sharp scissors or pruning shears. Remove any old, dead parts of roots.
Do this operation quickly, in a cool room; a damp basement is excellent.
After transplanting, keep the plants inside, for several days, then gradually expose to outdoor conditions. Thereafter, any insects that push through the bottom of the pot should always be cut away. You can also start pruning the tops lightly at this time, to develop a pleasing shape.
After this, your evergreens will require an inside planting every three to five years, and flowering and fruiting-runts yearly. Spring is the best time for each transplanting. Use only a slightly crier pot each time; any container with drain holes is suitable.
Always make up a fresh soil mixture, and prune the roots fairly vigorously. Cut back the thick roots irregularly and thin out the smaller ones to encourage the forming of a dense system.
Most bonsai experts use strictly arpnic fertilizers. You will probably have to work out your own fertilizing program to fit the needs of your specific plants. Most Chinese and Japanese growers advise very dilute applications of liquid fish fertilizer monthly or perhaps more often, except when the plant is dormant. But others say feeding only three or four times a year is plenty. Excessive feeding will result in too vigorous growth, and you’ll have a pot-splitting giant instead of an elegant dwarf.
If a tree looks weak, a sprinkling of high-nitrogen dried blood will perk it up. For regular feedings, very weak manure tea is as good as fish fertilizer. Occasional light sprinklings of manure compost are also excellent. Just enough fertilizer to keep the tree looking healthy is all that is necessary.
Water only when the soil feels dry to the touch, and don’t overwater. The soil should never be either bone-dry or waterlogged. In dry, hot weather, you may have to water two or more times a day. (Some Oriental growers, incidentally, use extremely porous soil and water five or six times daily, on the theory that starving the plant by leaching out fertility elements makes for slower, more compact growth.) Syringe the foliage now and then to remove dust and soot.
Bonsai do best outdoors, although many people have had fine success raising them entirely on sunny windowsills. They need abundant light, with some protection from the hot afternoon sun. Exposure to the elements makes the strongest trees, so let them spend as much time outdoors as possible—they provide a beautiful focus of interest for a patio, balcony or walled garden. You can, however, bring them indoors for a few days at a time if you put them in a cool spot away from heat sources.