Calcium is one of the most important minerals for both plants and microbes, probably the most important. Yet we know there is no such thing as one mineral being the most important, because they are all important. Interestingly, it is the most needed element by weight and volume for plants, and without sufficient calcium, nothing works. While nitrogen and potassium get a lot of attention, more and more focus are being put on calcium, particularly in organic horticulture.
Calcium helps plant cells communicate with each other by physically moving between cell membranes. Not only is it integral in the basic structure of plants, with a deficiency often showing up as thick, woody stems, it is largely responsible for the availability of
nutrients in plants and has a strong influence on microbial activity. In the book Mainline Farming For 21 Century, Dan Skow says “calcium is essential for its energy creation potential in the soil to release the other elements that cause a plant to grow.”
With enough calcium, roots and fine root hairs proliferate, stimulating soil microbes and building humus. This means that without enough calcium in the soil plants cannot access or utilize nutrients very well. Likewise, foliar fertilizers and microbial inoculants will have little effect if there’s a major calcium deficiency. You can waste a lot of time and money on fertilization if you do not have sufficient calcium.
We need a ratio of 10 Calcium to 1 magnesium ratio to create a soil that is free of compaction. The microbes need to be there in order for the calcium to be available, too. You can pile on bags and bags of calcium and you won’t get anywhere if you do not have the humus and microbes to make use of it.
A calcium shortage needs to be improved before other nutrient ratios will be fixed. For example, adding sulphur in the form of gypsum or ammonium sulfate can bind with excess magnesium and leach it, but you need sufficient calcium for this to happen efficiently.
Calcium is associated with nitrogen fixation and amino acid formation, so low calcium means the nitrogen cycle in the soil will also be less efficient and nitrogen will more easily leach.The unique micronized Lime/Gypsum have an average size between 5 – 15 μm (100 X smaller than 80% of agricultural lime). The small particle size ensures a complete reactive surface area in the soil. One kg of conventional lime has a reactive surface of ± 365 m2. 2,5kg micro fine Lime/Gypsum (5-15 μm) has a reactive surface of ± 60 000m2