Bonsai Soil

Raining & Draining

…………Avoiding the Root Rot

Bonsai soil is not ‘dirt’

Bonsai Soil

Critical Aspects

#1 The soil should allow rapid passage of

water completely through the pot

#2 When watering your Bonsai standing

water should not be observed

Bonsai Soil

Most Important characteristic

#3 The soil must

drain adequately

Soil Function

Stabilize the tree

Provide water, oxygen & nutrients

Attractive visual setting

Organic Soil Components

Decomposed bark

Potting soil – ‘Cactus Mix’

Compost

Leftovers – Mycorrhizae fungus

minimize Peat and avoid manure

Inorganic Soil

Components

Decomposed granite

Seramis

Haydite

Coarse sand

Arcillite

Grit

NO Diatomite –(Turface, Kitty Litter, Hi Dry)

Volcanic Soils

Pumice

Perlite

Vermiculite

Lava - Scoria

Japanese Soils

Akadama

Kanuma

Fugisuna

Hyuga

Kiryu

Keto

Green Moss

Increase soil water retention

Increase absorption time

May prevent oxygenation & hydration

Component

Characteristics

Size

Texture

Porosity

Water retention

Cation Exchange Capacity

pH

Organic characteristics

Decomposes

High ionic exchange

Loses core spacing

Leader root development

More plant energy on root development

Decrease root oxygenation

Thicker roots more difficult to repot

Inorganic Characteristics

Static

Low ionic exchange

Minimal water-nutrient retention

Maintains core spacing

More fibrous roots

Increase root oxygenation

Ease of repotting

Soil Component

Preparation

Sift

Size

Wash

Layering

Component Ratio

Organic-Inorganic

Species

Climate

Watering regime

Common General Recipe

1 part conifer bark

1 part porous clay (Akadama)

1 part non porous inorganic (grit)

David DeGroot Soil

40% Bark

20% 1/16” Crushed lava

20% 1/16” Crushed fired clay

20% 1/16” Crushed sand

Boon Manakitivipart Soil

1/3 Akadama

1/3 Crushed red lava

1/3 Pumice

Handful of agricultural charcoal and

crushed granite

Ryan Neil Soil

1/3 Pumice

1/3 lava(Scoria)

1/3 Akadama

References

1. Bonsai Techniques I, John Naka, pp 88-96

2. ABS. vol. 43, #4, pp 5-12

3. Bonsai, Deborah R. Koreshoff, pp 96-110

4. Bonsai Master Class, Craig Coussins, pp

28-36

5. Bonsai Master Class, Peter Chan, pp20-23

6. Living Art of Bonsai, Amy Liang, pp 178-188

7. Growing Bonsai, Ken Norman, pp 70-71