In the old soil the roots of the 'Chabo-hiba' preferred to grow over the surface rather than deeper in the pot. This was a sure sign that something was wrong with the soil recipe.
Several years after a routine repotting the roots appeared weak and sparse. Part of this was due to the large block of centuries-old soil in the center, but a greater part was clearly due to the poor soil recipe. At successive repottings we are gradually reducing the central block of old field soil, and replacing it with the new recipe.
Having had about one third of the old field soil removed and the soil recipe changed to one high in Akadama and lava, the roots are still thick and vibrant four years later. This increase in root health led directly to a corresponding and very evident increase in the health of the foliage.
