The third essential element in the biochemical sequence necessary for healthy plant growth is Calcium, which bears the atomic number 20 and is referred to by the symbol Ca.   We are familiar with how essential Calcium is to our own health, so it is not surprising that this element plays an equally vital role when it comes to plant health.  Leading agricultural consultant and author of “The Biological Farmer’, Gary Zimmer dubbed Calcium as “the trucker of all minerals”, as it regulates the transport of other nutrients into the plant.

There are many different roles that Calcium plays depending on where we focus:

  • In the Soil – Helps to flocculate and create good soil structure, this influences the oxygen in the soil which intern allows both the microbial life to flourish and the plants roots systems to develop as we would like it to.
  • In the Plant – Found hugely in the cell walls and is responsible for how strong they are which relates directly to resisting insect and fungal attacks.
  • In the Fruit – Because of it being “the trucker of all minerals” it is directly related to building the nutrient density in food and of course with this the flavour spectrums that we are after in wine grapes! In fresh fruit it has the ability to extend shelf life tremendously.

BRIX readings, the test for total sugars, minerals and other dissolved nutrients in a liquid, can give a good indication of whether the plant has sufficient Calcium as this element builds BRIX levels.  A high reading denotes high levels of nutrients and hence a nutrient dense product.

Calcium is essential in the physiology of plant cells; it functions as a signal for many cellular processes and is involved in the activation of certain plant enzymes.  Calcium is involved in both cellular structure and cell division.  One of its key roles in soil is to reduce Nitrate Nitrogen in combination with carbon to form amino acids that create proteins; this of course is a great source or stored energy for the living soil system. Luxury levels of Calcium in the soil are needed for the natural Nitrogen system to work properly.  Without sufficient Calcium a plant will be stunted, compromising fruit size and yield.

The Biodynamic preparations BD 503, BD 504 and BD 505 all have a direct influence on how Calcium works in the natural system. It is essential to get these BD preps into the system, one of the best ways to do this is used them in production of compost. We also use them through our Field Broadcaster. For more on the BD preps Click here!

Most agricultural soils in the Western Cape are out of balance due to chemical farming.  At Avondale, we take soil samples to check if maintenance applications of Calcium will be necessary.  If so, we’ll apply natural forms of Calcium such as Calcitic Lime, Dolomitic Lime, Gypsum or Rock Phosphate in autumn before the rains.  Of course, we also pay much attention to having a thriving ecosystem in the soil so that an abundance of micro-organisms can do their work of digesting and solubilising the Calcium, making it readily available to our vines.