The term bonsai originates from Japanese and is a combination of bon (tray/pot) and sai (plant/planting) — literally translated, it means “tree in a pot.” Contrary to a widespread misconception, a bonsai is not a genetically dwarf plant species. It is a normal, often centuries-old tree from the wild, kept small and well-formed through consistent horticultural care.

The Three Pillars of Philosophy:

• Wabi-Sabi: The beauty of imperfection, impermanence, and incompleteness. A bonsai shows traces of age, weather, and resilience.

• Imitation of Nature: The goal is not to breed a lab-styled tree, but to accurately mirror the majestic image of an old tree from the mountains or a coastal cliff in miniature scale.

• Patience and Mindfulness: A bonsai is never “finished.” It is a living work of art that develops alongside its artist over decades.

Choosing the wrong location is the #1 reason beginner bonsai die. Before buying or styling a tree, you must understand this fundamental biological division:

A. Outdoor Bonsai

• Which trees? All native and temperate tree species (maples, pines, larches, oaks, beeches, junipers).

• Requirements: They must live outdoors. They need the seasonal cycle, wind, rain, direct sunlight, and especially the winter frost period (dormancy) to survive.

• Indoors: They will inevitably die within a few weeks because their metabolic rhythm is disrupted.

B. Indoor Bonsai

• Which trees? Tropical and subtropical plants (e.g., Ficus Ginseng/Retusa, Carmona microphylla, Sageretia, Jade plant).

• Requirements: They cannot tolerate frost, but can survive in heated rooms if placed in an extremely bright spot (south-facing window).

• Summer Tip: Even indoor bonsai love spending May through September protected outdoors.

No other maintenance task requires as much sensitivity as watering. More trees die from daily, mindless overwatering (waterlogging) than from drought.

The Golden Rhythm:

1. Never water by the calendar: Do not water rigidly every day at 6 PM. Water demand depends on temperature, wind, humidity, tree species, and substrate.

2. The Finger Test: Insert your index finger about 1 to 2 centimeters deep into the substrate. If the soil feels slightly damp and cool there, wait with watering. If it is dry, water thoroughly.

3. The Technique: Water from above with a fine rose until the water runs abundantly out of the drainage holes of the pot. This pushes old, consumed gases out of the substrate and draws fresh oxygen into the roots.

Planting a bonsai in commercial potting soil from the hardware store risks suffocating the tree. Potting soil is too fine, compacts quickly, retains too little oxygen, and tends to mold and waterlogging.

The Anatomy of True Bonsai Substrate:

A professional substrate is coarse-grained, structurally stable, and consists almost entirely of mineral components:

• Akadama: Dried, crushed Japanese volcanic clay. It stores water and nutrients perfectly and indicates when to water through color changes (light = dry, dark = moist).

• Pumice: A lightweight volcanic rock that ensures permanent aeration and oxygen supply in the root zone.

• Lava: Heavier than pumice, stores minerals, and gives the heavy root ball stability in the shallow pot.

Since a bonsai lives in a very limited pot with little soil, the nutrients in the substrate are depleted within a few weeks. Without fertilization, the tree will slowly weaken.

The Golden Fertilization Rule:

• When to fertilize? Exclusively during the main growing season – from spring (bud break) into late summer (approx. September). Fertilization is completely stopped in winter as the tree enters dormancy.

• Organic vs. Mineral Fertilizer:

  • Organic solid fertilizer (e.g., in pellets or pressed cakes like Bio-Gold) is placed directly on the substrate. Nutrients are gently released with every watering, fostering soil microbial life.

  • Liquid fertilizer acts very quickly, but should only ever be applied to pre-moistened soil to avoid burning the fine roots.

Pruning is fundamentally divided into two categories: coarse structural pruning (during winter dormancy) and fine maintenance pruning (during the growing season).

Pinching (Shortening Shoot Tips):

• When deciduous trees (like maples or elms) push new growth in spring, shoots often grow long and uncoordinated in search of light.

• To keep the silhouette of the bonsai compact and promote internal ramification, pinch or cut soft, long new shoots back to one or two pairs of leaves.

• Tools: Use exclusively clean, razor-sharp concave cutters or bonsai shears so wounds heal quickly without unsightly bark tears.

Many beginners fear root pruning – yet it is absolutely vital for the bonsai’s health.

Why Prune Roots?

In a shallow pot, roots grow in circles and completely fill the space. After a few years, the root ball becomes so dense that water can no longer penetrate (the tree is “pot-bound”).

• The Principle: During each repotting, about 20% to 30% of the total root ball – especially thick, downward-growing anchor roots – are trimmed with sharp shears.

• The Effect: This targeted pruning forces the tree to form fine, nutrient-absorbing capillary roots directly at the base of the trunk (Nebari). This keeps the tree vigorous, small, and compact.

The perfect time to repot is early spring (March), just before the buds swell on the tree and sap flow begins.

The Process Overview:

1. Removal: Gently lift the tree out of the pot.

2. Root Care: Carefully comb out old, exhausted soil from the root ball using a root hook or chopstick.

3. Pruning: Trim the outer and bottom roots.

4. Pot Preparation: Cover drainage holes with mesh, insert anchoring wires, and add a thin drainage layer (coarse lava/pumice).

5. Anchoring & Filling: Secure the tree firmly in the pot with wire (so it won’t wobble in the wind), pour in fresh substrate, and poke it firmly between roots with a wooden stick to eliminate air pockets. Finally, water thoroughly.

Wire is the bonsai artist’s most important tool for giving branches a targeted direction and simulating the look of a centuries-old natural tree.

Basic Rules for Safe Wiring:

• Material: Anodized aluminum wire or soft-annealed copper wire is used.

• The Technique: The wire is wrapped around the trunk or branch at a 45-degree angle. It must never be applied too tightly, otherwise, it will cut into the bark during thickness growth and leave ugly scars.

• Ideal Timing: Deciduous trees are best wired in late autumn or winter (leafless); conifers in late autumn or early spring.

• Monitoring: As soon as the branch has assumed the desired shape or the wire threatens to bite into the bark, it must be carefully cut off in small pieces using a special wire cutter – never unwrap it!

Knowing the typical pitfalls of bonsai art saves a lot of frustration and protects trees from an early demise.

The 4 Deadly Sins:

1. The Watering Mistake (Too much or too little): Either the tree drowns in permanently wet soil (root rot) or it dries out because the surface looks dry while the inside might still be wet – or vice versa. Rule: Always check the depth with your finger.

2. Wrong Location: Trying to overwinter an outdoor maple in a warm living room. (It loses its internal clock and dies).

3. Delayed Repotting: Leaving the tree in the same exhausted soil for 10 years deprives it of any nutritional foundation.

4. Impatience During Styling: Trying to bend thick branches with force without prior cutting or scoring, causing them to snap. Patience and step-by-step building are the keys to success.