“Meso elements” are calcium, magnesium and sulphur that plants need to uptake in intermediate measures in respect to macro and micro nutrients.
Calcium is a natural component in most soils. In most soils it can be found in the form of carbonate, phosphate, silicate and in organic matter. In the soil it binds with other nutrients and reduces solubility of both. From a physiological point of view, calcium is an essential component of protopectines which are to be found in the vegetal cell walls and is directly responsible for vegetal and reproductive tissue consistency (flowers and fruits).
Calcium contribution increases consistency and mechanical resistance of tissues during ripening, handling, transportation and storage.
Main causes for calcium deficiency could be due to an insufficient supply in the soil (sandy and loose); unavailability due to a high acid pH and an excessive amount of sulphur or phosphorous that bind with calcium, forming insoluble salts (calcium sulphate and tricalcium phosphate). Other reasons could be cases of antagonism with nitrogen under ammoniacal ion form (NH4+) , with potassium under ion form (K+) and with magnesium (Mg++).
Calcium deficiency shows on young leaves and shoot ends because they are practically non-moving elements of the plant and they need periodic applications with every new emission, at each blossoming and at every fruit setting cycle of re-blossoming crops. In fruit trees calcium deficiency (bitter-pit and cork spot in pomaceae crops, blossom and rot in tomatoes, cavity spot in carrot, white translucent blotches, apical necrosis of the cluster in certain grape varieties , leaf tip-burn on lettuce and cabbages, necrotic margin in poinsettia etc..) are evident in unbalanced plants, with excessive vigour and poor production.
The plants are unable to find all the calcium they need from the soil.
It could be present but probably blocked and not available, sometimes if it is free it could be in a hydrated from up to the point of creating a very big molecule, and the plant roots have difficulty with uptake, having to waste a lot of energy on it. It is therefore very important to be able to detect these above mentioned symptoms in order to intervene.
If soil is alkaline it needs to be acidified with acid pH fertilisers (nitric acid, phosphoric acid, urea phosphate) in fertigation system with frequent low dosage applications, in order to keep the soil surrounding the roots in optimal condition and to keep the calcium available.
If fertigation system is not possible and in case effective soil applications can not be made, the best way to apply calcium will therefore be by foliar application to avoid any chemical complications that could result in the soil. Not less important is the chemical form in which the calcium is applied to soil: calcium nitrate is better in liquid form with an acid pH of the solution (with a slight surplus of nitric acid). By foliar application, it is better to use ingredients with co-adjuvants that protect and carry calcium to the plant like complexing ingredients (lignin sulphonates) or products that have a strong bond with calcium and nitric ions, protecting them against reactions and carrying them.
Magnesium is an essential ingredient of the central chlorophyll atom and plays a key role in photosynthesis. It also controls sugar, protein, fat and vitamin formation. It carries phosphorous through the plant (their action is synergic) and is an antagonist of potassium and calcium. Like calcium it circulates very little and does not pass from old to young vegetative and productive tissues, so, if there is a lack magnesium availability in the soil then applications should be made periodically with every new vegetal emission.
Biokimia “Mesoelement” products can satisfy all needs regarding calcium, magnesium and sulphur. The latter being present in most ingredients as a raw material.
Even in this case an complete knowledge of the cultivated soil is important by effecting analysis and relying on past experience. Advice remains the same and is that of keeping nutritionally well balanced plants guaranteeing them not only macro nutrients but also calcium, magnesium, sulphur and trace elements.