At Avondale, we draw on the science of the Albrecht System of soil balancing to promote and sustain healthy life in our soils. Dr William Albrecht was one of the world’s foremost authorities on the impact of soil health on the health of plants, animals and people. He proposed that there was an ideal pH in the soil that would promote the optimum nutritional uptake for crops. The 0 to 14 pH scale measures the acidity (0 to 6.5) or alkalinity (8 to 14) of a substance. Albrecht’s studies showed that the ideal pH for soil is between 6.5 and 7. This slightly acidic to neutral pH is most conducive to balanced growth and nutrient availability. If a soil is too acid or too alkaline certain nutrients in the soil correspondingly become unavailable to plants. However, Albrecht stressed that achieving this pH balance is not the be all and end all of soil balancing. That it is all about broad spectrum nutrition and balance. He also stressed it is not a numbers game, but rather about ratios and balance. An example of this is the importance of trying to achieve specific calcium to magnesium ratio. Depending on the soil type, the calcium to magnesium ratio can vary from 7:1 in heavy soils to 4:1 in light sandy soils. Too much magnesium in the soil will promote compaction and anaerobic conditions that shut down the availability of other minerals such as potassium and make life in the soil a struggle for the micro-organisms. Hence, in heavy soils we aim for a larger proportion of calcium because this will make it more aerobic. On the other hand, too much calcium in a lighter soil leads to highly aerated, ‘sandy’ conditions that cannot hold moisture and close down the availability of other important nutrients. In this situation we would increase the proportion of magnesium to make the soils “tighter”.
The most important thing though is not to get caught up in the numbers but to keep an eye on the ratios and balance. Be mindful that everything is interconnected and one can easily create an imbalance unintentionally if one loses sight of the bigger picture.
At Avondale, we take soil samples every two years from every vineyard block. The analyses that we do include testing the full spectrum of nutrients including the trace minerals that conventional farmers do not consider at all. We only use natural sources of nutrients and minerals to balance our soils as well as various biodynamic preparations so that whatever we might add to our vineyard ecosystem is easily accepted and accessible to the communities of plant and micro-life. In this we way, we build and maintain the fertility of soils in a natural way so that we make our wines from healthy, balanced grapes. Keeping visiting this blog for more posts on how we maintain balance in the soils and how we use biodynamic preparations to sustain a healthy, living vineyard ecosystem.