TerraSai-Rhodo has a special mixing ratio of high-quality organic and mineral components and was developed especially for azaleas. Due to the use of oak bark compost, the substrate reacts slightly acidic and a low pH value is established. This is very conducive to healthy azalea growth.
Our TerraSai mixes draw on prior experience gained before baked clay granules (Akadama) entered the German market in the 1990s. With this expertise, we developed new in-house mixtures in 2011. The various new soils were tested and examined by Dipl. Ing. Ulli Fendrich*. The test result is convincing! All soils are characterized by a very good structural stability, water and air flow as well as buffer capacity (pH value, nutrient concentration). Of course, various biotic and abiotic factors affect the substrate over time. The type of fertilizer and the nature of the irrigation water can also lead to physical and chemical changes in the soils. However, the TerraSai soils show themselves to be very stable and tolerant to these influences. Especially in the comparison of the buffer capacity and the long-term structural stability, advantages are shown compared to the clay granulate (Akadama). With Akadama in particular, deposits and silting due to fine clay particles at the bottom of the shell occur with increasing age of the substrate and especially after exposure to frost. This leads to waterlogging or lack of air and is detrimental to root growth. Depending on the plant species and the stage of development of the bonsai, we offer seven different soil mixtures. These are individually adapted to the individual needs of the respective plant group and have proven themselves in practice for years. In our own bonsai production and further cultivation we use today exclusively TerraSai soils. * Ulli Fendrich has studied with Prof. H.-P. Blume (co-author of the textbook of soil science by Scheffer/Schachtschabel).
