Chemical elements are utilised by plants and are essential for plant growth.
At one time, water was thought to be the sole nutrient needed by plants. It was later found that certain "earth substances" were beneficial
for plant growth.
Fertilisers put these "substances" called nutritional elements back into the soil, which are then utilised by the plant.
All living plant needs three essential nutritional-elements in order to thrive: NITROGEN, PHOSPHORUS and POTASSIUM
Functions these elements have in the plant?
Nitrogen (N): Nitrogen plays a key role in many metabolic reactions. Because nitrogen is contained in the chlorophyll molecule
(green substance in plants), a deficiency of nitrogen will result in chlorotic (yellowing) condition of the plant. Nitrogen is also a
structural constituent of cell.walls.
Phosphorus (P): Phosphorus has been described as ubiquitous in the plant, being involved in nearly all-metabolic processes.
It plays a vital role in the life cycle of plants and is important il1 reproductive growth, promoting early maturity and fruit
quality, as well as seed formation.
Potassium (K): Potassium plays an important role in the water relations in the
plant. Adequate potassium causes cell walls to be thicker and provides more tissue
stability, which normally improves resistance to lodging, pests and diseases. Fruits
and vegetables grown with adequate potassium seem to have a longer shelf life in
the grocery store.
Fertilisers indicate the ratio between. these elements (N:P:K) according to the
specific needs for use:
NITROGEN, PHOSPHORUS and POTASSIUM.
Most commercial Fertilizers contain all three in various proportions, and at a variety
of concentrations. If you look at the contents listed on fertilizer packs you will see the
N (NITROGEN) P (PHOSPHORUS) K (POTASSIUM) followed by three numbers,
these numbers represent the ratio between the three nutrients, and the relative
strength of the fertilizer.
The higher the number the stronger the concentration of the nutrient.
In most cases two numbers in brackets follow these numbers (2:3:2 (22», this
number represent the percentage of active ingredients of the fertilizer, the balance is
made up of non nutritional fillers.
NKP 2:3:2 (22)
2 parts Nitrogen
3 parts Phosphorus
2 parts Potassium
22% active ingredients (220g/kg)
220q/kq (Active inqredient)
7 (Total Parts) = 31,4g/kg (Mass of one part)
220g/kg active Ingredients
NPK 3:1:5 (15)
150g/kg active Ingredients
Colorless, tasteless, odorless, gaseous element, that constitutes 78% of the
atmosphere by volume, stacking up 35 million kg over every acre of land.
" Chemical symbol:
Focal element in the nitrogen cycle by which nitrogen passes though successive
stations in air, soil and organisms to achieve fixation. A governing factor in the decay
of carbonaceous materials. Amino nitrogen takes up 6% of compounds, eve'rycell in
plant life requires nitrogen in the right form, 5% of organic matter in soil is present as
nitrogen, this is broken down by micro-organisms and the nitrogen can the be used
by the plant. Plants take up nitrogen through their roots, as pure nitrogen makes up
about 78% of the earth's atmosphere. Some plants as: Alder and Acacia can meet
their need for nitrogen from the air, with the help of so called root nodule bacteria.
Nitrogen joins carbon, hydrogen and oxygen as a main constituent of the animal
body, other than the skeleton.
Nitrogen is responsible for shoot development and foliage production, in short, for
. growth. Too little nitrogen will result in a plant that will not thrive, with small and
possibly distorted yellow leaves and a washed-'out appearance, With no nitrogen at
all an established plant could be dead within a year, by contrast to much nitrogen will
result in rapid growth with large leaves, plump shoots that are full of water and
consequently very easy to snap.
A solid nonmetallic element of the nitrogen family is existing in at least two allotropic
forms, one yellow poisonous, inflammable, and luminous. The other red less
poisonous and inflammable.
Phosphorus occurs naturally mainly in organic compounds such as protein and
bones, the release in soils depends on decomposition of these organic compounds,
contained in all tissues with concentrations most pronounced in young plants, seed
Super phosphate, triple-super phosphate, rock phosphate, and organic fraction
phosphates, proteins, phospholipids etc. are labile-undergo chemical and physical
changes while not necessarily available, essential for building sound bones and
teeth in the animal body, and for assimilation of carbohydrates and fats, necessary
for enzyme activation. Essential for the development and proper functioning of roots,
also encourages the fattening of woody trunks and branches, and helps to establish
appropriate conditions for the production of foliage and flower buds, and to make
nucleic acids. It also enhances the plant's resistance to stress and diseases, Weak
growth with pale green leaves, and a low resistance to illness and frost could be the
result of a lack of phosphorus. Phosphorus is taken up through the roots and its
availability depends largely on the pH value of the soil, minerals present in clay,
which also absorbs phosphorus can reduce its availability to the plant.
A silver-white soft light low-melting univalent metallic element of the alkali metal
group, abundant in nature esp. combined in minerals (see Mendeleyeff Periodic
Table pf Elements)
Potassium is a highly reactive element that forms part of many mineral compounds
but does not occur in pure form in nature and is not found in organic compounds. It
controls most metabolic procedures in plants and plays an important role because or
its osmotic effect. A catalyst and prime requirement, in chlorophyll construction.
A governor for taking free nutrients from the air -carbon, hydrogen, oxygen. Needed
so plants can make starches, sugars, proteins, vitamins, enzymes of cellulose,
dangerous to microorganisms when embodied in muriate of potash in animal life.
Promotes normal growth and muscle function, also a cell regulating element
regulates osmotic pressure in cellular tissue and fluids. Potassium is the main agent
for the development of fruit and flowers. By increasing the amounts of potassium in
fruit bearing and flowering bonsai which fruit or flower poorly will increase their
performance the next spring. Potassium also helps hardening of late growth in
preparation for winter. In non-fruit bearing or flowering trees, insufficient potassium
results in winter die back. A few hands full of hard wood ash are an excellent source
of cheap potassium.
CALCIUM. MAGNESIUM and SULPHUR
Calcium and magnesium are considered as elements of secondary importance in the
industry and marketing of the commercial fertilizers, but the truth is that for the soil
and for plants calcium and magnesium are primary in importance both quantitatively
and alsofor their bio-chemicalsignificance. .
A deeper look into every living body, including the human being, discovers the fact
that nothing can live without calcium and magnesium. The skeletons of human
beings and those of all fully developed animals are built of tri-calcium phosphate.
The immense world of microbes and all the bio-chemical processes require certain
amounts of calcium and magnesium. There may not be a green plant without the
action of magnesium, for magnesium controls the development and the biochemistry
of the chlorophyll molecule; subsequently, there is no photosynthesis, namely,.any
food for other forms of life without the work of magnesium. Every agricultural product
contains certain amounts of calcium and magnesium, and logically a fertile and
productive soil must contain calcium and magnesium -in fact, it holds very large
amounts of both of these two elements. It has been proved that calcium is the most
important element among all the plant food elements. It is as important to eliminate
the deficiencies of these two elements as it is to avoid the excesses of the same in
A silver white bivalent metallic element of the alkaline earth group occurring only incombination
Calcium occurs in the soil in carbonate, sulfate or phosphate. A plant nutrient, that
should occupy between 65 and 70% of the positions on the soil colloid in terms of
the exchange capacity. At the proper saturation improves soil texture, makes
phosphorus and micro-nutrients more available, and improves the environment for
microorganisms, helps plants form better root systems, stems and leaves for efficient
use of sunlight energy, water, carbon dioxide, nitrogen end mineral nutrients.
Essential for building normal bones and teeth, important in blood coagulation, and
lactation, enables heart, nerves and muscles to function, regulates permeability of
tissue cells in animals.
Most important fertilizer element, it plays an important role in cell production and the
growth of roots. It is absorbed through the roots. Lime helps to neutralize acid soil
and has a beneficial effect on the structure of the soil, on the activity of
microorganisms and on the resulting availability of other nutrients. Calcium
deficiency is characterized by weak growth, a low resistance to illness or yellow
A silver-white, light malleable ductile metallic element.
Occurs abundantly in nature as an alkaline earth, used in many industrial processes,
including photography, pyrotechnics, MgO used in fertilizers, cement insulation, in
medicine magnesia is an antacid and mild laxative.
In soils Magnesium has 1.666 times as much exchange capacity as an equal amount
of calcium, high magnesium and low calcium permits organic residue to decay into
alcohol, a sterilant to bacteria, it should occupy between 10 and 20% of the soil's
In the human body, it is essential for nerve and muscle activity and in bone structure,
aids in growth promotion.
SOME ASPECTS OF MAGNESIUM IN THE SOil:
* It is contained in minerals such as biotite, dolomite and chlorite.
* Deficiencies occur most often in coarse-textured, acid soils.
* It occurs as a cation (Mg ++)
SOME FUNCTIONS OF MAGNESIUM IN PLANT GROWTH ARE:,
* A mineral constituent of chlorophyll.
* Actively involved in photosynthesis.
* Aids in phosphate metabolism.
* Activates several enzyme systems.
If a plant lacks magnesium its older leaves will turn yellow with the veins remaining
A nonmetallic anion element that occurs either free, or combined esp. in sulfides and
Is a constituent of proteins and exists' in allotropic forms, including yellow
orthorhombic crystals. Resembles oxygen, yet less active and more acidic. Its
release in soils is governed by the size of the organic matter bank that accounts for
its transformation under the auspices of the decomposers of the biotic pyramid which
take proteins and organic combinations -of which hydrogen and sulfur are simple
forms --and turns them into sulfates and sulfites essential to formation of sulfur
containingproteins,a constituentin thiamine,biotin,glutathione. .
It is available in quantity in the air in the form of sulfur dioxide and is washed into soil
by rain and it can be ignored in fertilizing.
ONLY SMALL QUANTITIES OF MINERALS ARE NEEDED
In the Diagnosis of Mineral Deficiencies in Plants, by T. Wallace. The principle is
stated in the following words: "Since catalysts are not used up in the chemical
reactions which they promote, we can understand how it comes about that quite
small or even minute quantities of the 'trace elements' iron, manganese, boron, zinc
and copper, may nevertheless be essential to the plant's health and growth"
Iron may be used as an example. As the most copiously required trace minerals, an
iron level of 80 PPM is nevertheless considered fully adequate in the tissues of many
A halogen element that is isolated as a heavy greenish yellow gas of pungent odor.
i Chemical symbol:
Especially a part of the compound sodium chloride is regarded essential to the
growth of some plants. Under some conditions, an excess of chlorine causes chlorite
spots on tobacco leaves and other plants.
A nonmetallic element
The simplest and lightest of elements, colorl~ss, odorless, highly flammable diatomic
gas, the base for acidity in soil systems.
A silver white soft waxy ductile element of the al~ali metal group.
Occurs abundantly in nature in compound form very active as a cation a cell-
regulating element that governs osmotic pressure in cellular tissues and fluids.
A metallic element that resembles chromium and tungsten in many properties.
Essential for plants in trace amounts, 0.01 to 0.10 PPM governs microorganisms
needed to interrelate. Best illustrated in animal health, where an excess makes
copper unavailable, de-pigments hair and accounts for severe scouring deficiency in
animals created by excess sulfur, which slows cellulose digestion a deficiency of
molybdenum slows conversion of nitrogen to protein. Molybdenum helps to control
nitrogen metabolism. The yellowing and malformation of young leaves usually
indicate a deficiency
A bluish white crystalline bivalent metallic element.
Of low to .intermediate hardness, ductile when pure. Absolutely vital (along with
molybdenum) to the life process of soil microorganisms, esp. Azotobacter. A non-
symbiotic nitrogen-fixing microorganism, aids in the promotion of normal growth and
tissue respiration in animals, interrelated with insulin and vitamin B1 deficiencies,
important in the development of normal hair coat, now regarded as a dietary
essential and constituent of carbonic anhydrase. Zinc controls the activities of
enzymes and the development of hormones. It also plays a role-in photosynthesis.
SOME COMMON ZINC SOURCES:
SOURCE % ZN PERCENT
Zinc sulfates (hydrated)
Basic zinc sulfate 55
Zinc carbonate 52
Zinc sulfide 67
Zinc fritz Variable
Zinc phosphate 51
Zinc chelates 9-14
Other organic 5-10
A trivalent metalloid element found in nature only in combination.
Required for translocation of sugar, regulates flowering and fruiting, cell division and
cell wall formation, salt absorption, carbohydrate metabolism, water use and nitrogen
assimilation in plants, functions in the synthesis of glycogen and the maintenance of
body fat in animal life.
A heavy malleable duCtilemagnetic silver-white metallic element.
In biology, an indispensable carrier of c;:>xygenrequired in the production of
chlorophyll and as an aid in the prevention of chlorosis. A difficult nutrient to supply
to plants in an available form to human beings and animals, essential for hemoglobin
formation because divalent iron occupies a central position in the hemoglobin
structure, essential in oxygen transfer and cell respiration, and aids in blood cell
development, and in the prevention of anaemia.
A grayish white, hard and brittle metallic element.
Resembles iron, albeit diamagnetic, aids the oxide enzyme in carrying oxygen and
enters into the oxidation and reduction reactions in plant life required for
carbohydrate metabolism and seed formation. In animal life, it is an essential
biocatalyst in normal growth and bone development and maintenance. Deficiency in
plants is indicated in brown spots appearing on older foliage.
Reddish ductile metal.
In agriculture, vitally important to root metabolism helps form compounds and
proteins, amino acids and many organic compounds, a catalyst or part of enzyme
systems; helps produce dry matter via growth stimulation, prevents development of
chlorosis, rosetting and die-back. In animal life, essential for catalytic conversion of
iron into red blood cells, and assists in tissue respiration. A copper deficiency is
visible by white tips to the leaves.
A white non-metallic anion element
It is a proven fact that silica plays an important fertilizing role in the plant kingdom.
Tests have shown an improvement in cultivation following the addition of silicates.
Silica also functions as a vital element in protecting plants against mold penetration,
and it has been found to influence the use of other ingredients useful to plant
metabolism. A rich supply of natural organic silicates can be found in eguisetum
arvense, the source of vegetal silica. Better known as horsetail, spring horsetail, or
scouring rush, this perennial grow.s wild in all temperature zones of our planet, It
belongs to a small group of plants known as pteridophyta, which is distinguished as
non flowering and non-seed-bearing. Horsetail thrives on clay-like sandy soils. It
occurs mainly in marsh lands but can be found in woods and forests, moist fields,
meadows and along the sandy shores of creeks and streamlets. Some varieties
have adapted to other environments, living along roadside and stony ground.
Silica deficiency may exist if your diet consists of too many refined foods. Silica is
abundant in the shell of brown rice, in leafy greens and bell peppers. When food is
processed, silica is unfortunately removed. Fiber is usually the first to be cut or
washed away, and along with the fiber, the silica. Stripped cereals and other
processed foods have decreased silica supplies. This massive loss of natural silica
has been paralleled by an increase in degenerative diseases