Plant Nutrition
Macronutrients
Macronutrients can be broken into two more groups: primary and secondary nutrients.
The primary nutrients are Nitrogen (N), Phosphorus (P), and Potassium (K). These major nutrients usually are lacking from the soil first because plants use large amounts for their growth and survival.
The secondary nutrients are Calcium (Ca), Magnesium (Mg), and Sulfur (S). There are usually enough of these nutrients in the soil so fertilization is not always needed. Also, large amounts of Calcium and Magnesium are added when lime is applied to acidic soils. Sulfur is usually found in sufficient amounts from the slow decomposition of soil organic matter, an important reason for not throwing out grass clippings and leaves.
Macronutrients
Macronutrients can be broken into two more groups: primary and secondary nutrients.
The primary nutrients are Nitrogen (N), Phosphorus (P), and Potassium (K). These major nutrients usually are lacking from the soil first because plants use large amounts for their growth and survival.
The secondary nutrients are Calcium (Ca), Magnesium (Mg), and Sulfur (S). There are usually enough of these nutrients in the soil so fertilization is not always needed. Also, large amounts of Calcium and Magnesium are added when lime is applied to acidic soils. Sulfur is usually found in sufficient amounts from the slow decomposition of soil organic matter, an important reason for not throwing out grass clippings and leaves.
Micronutrients
Micronutrients are those elements essential for plant growth which are needed in only very small (micro) quantities . These elements are sometimes called minor elements or trace elements, but use of the term micronutrient is encouraged by the American Society of Agronomy and the Soil Science Society of America. The micronutrients are Boron (B), Copper (Cu), Iron (Fe), Chloride (Cl), Manganese (Mn), Molybdenum (Mo) and Zinc (Zn).
Trace Elements (Micronutrients) in Plants
Trace elements play a vital role in plant nutrition. Although plants only require trace elements in minute quantities the absence or unavailability of one or more trace element will cause depressed growth of pasture and crops, and can also cause nutritional imbalances in plants and animals. Alternatively, an excess can potentially have a negative influence on optimum development.
Trace element deficiencies are not generally recognized, even by many investigators, because too much stress has been placed on visual, clinical symptoms, such as chlorosis of leaves or abnormal growth. These symptoms are of the greatest value in indicating the presence of nutritional deficiencies, but it must be appreciated that not all deficient plants show them. Deficiencies not acute enough to show visual signs may be severe enough to halve the potential yield. Thus plant tissue testing is the best way to determine nutrient deficiencies.
Micronutrients are those elements essential for plant growth which are needed in only very small (micro) quantities . These elements are sometimes called minor elements or trace elements, but use of the term micronutrient is encouraged by the American Society of Agronomy and the Soil Science Society of America. The micronutrients are Boron (B), Copper (Cu), Iron (Fe), Chloride (Cl), Manganese (Mn), Molybdenum (Mo) and Zinc (Zn).
Trace Elements (Micronutrients) in Plants
Trace elements play a vital role in plant nutrition. Although plants only require trace elements in minute quantities the absence or unavailability of one or more trace element will cause depressed growth of pasture and crops, and can also cause nutritional imbalances in plants and animals. Alternatively, an excess can potentially have a negative influence on optimum development.
Trace element deficiencies are not generally recognized, even by many investigators, because too much stress has been placed on visual, clinical symptoms, such as chlorosis of leaves or abnormal growth. These symptoms are of the greatest value in indicating the presence of nutritional deficiencies, but it must be appreciated that not all deficient plants show them. Deficiencies not acute enough to show visual signs may be severe enough to halve the potential yield. Thus plant tissue testing is the best way to determine nutrient deficiencies.
Macronutrients
Phosphorus (P)
• Like nitrogen, phosphorus (P) is an essential part of the process of photosynthesis.
• Involved in the formation of all oils, sugars, starches, etc.
• Helps with the transformation of solar energy into chemical energy; proper plant maturation; withstanding stress.
• Effects rapid growth.
• Encourages blooming and root growth.
• Phosphorus often comes from fertilizer, bone meal, and superphosphate.
Potassium (K)
• Potassium is absorbed by plants in larger amounts than any other mineral element except nitrogen and, in some cases, calcium.
• Helps in the building of protein, photosynthesis, fruit quality and reduction of diseases.
• Potassium is supplied to plants by soil minerals, organic materials, and fertilizer.
Calcium (Ca)
• Calcium, an essential part of plant cell wall structure, provides for normal transport and retention of other elements as well as strength in the plant. It is also thought to counteract the effect of alkali salts and organic acids within a plant.
• Sources of calcium are dolomitic lime, gypsum, and superphosphate.
Magnesium (Mg)
• Magnesium is part of the chlorophyll in all green plants and essential for photosynthesis. It also helps activate many plant enzymes needed for growth.
• Soil minerals, organic material, fertilizers, and dolomitic limestone are sources of magnesium for plants.
Sulfur (S)
• Essential plant food for production of protein.
• Promotes activity and development of enzymes and vitamins.
• Helps in chlorophyll formation.
• Improves root growth and seed production.
• Helps with vigorous plant growth and resistance to cold.
• Sulfur may be supplied to the soil from rainwater. It is also added in some fertilizers as an impurity, especially the lower grade fertilizers. The use of gypsum also increases soil sulfur levels.
Micronutrients
Boron (B)
• Helps in the use of nutrients and regulates other nutrients.
• Aids production of sugar and carbohydrates.
• Essential to actively growing tissue in new growth.
• Necessary for pollen viability and good seed set.
• Essential for seed and fruit development.
Copper (Cu)
• Important for reproductive growth.
• Aids in root metabolism and helps in the utilization of proteins.
• Important in photosynthesis, protein and carbohydrate metabolisms and nitrogen fixation.
Chloride (Cl)
• Aids plant metabolism.
• Chloride is found in the soil.
Iron (Fe)
• Essential for formation of chlorophyll.
• Sources of iron are the soil, iron sulfate, iron chelate.
Manganese (Mn)
• Functions with enzyme systems involved in breakdown of carbohydrates, nitrogen metabolism and protein production.
• Soil is a source of manganese.
Molybdenum (Mo)
• Essential for nitrogen fixation by nodule bacteria in legumes and for nitrogen conversion to amine form and for nitrogen assimilation.
• Soil is a source of molybdenum.
Zinc (Zn)
• Essential for the transformation of carbohydrates.
• Regulates consumption of sugars.
• Part of the enzyme systems which regulate plant growth.
• Affects plant maturity.
• Sources of zinc are soil, zinc oxide, zinc sulfate, zinc chelate.
Cobalt (Co)
• Essential for nitrogen fixation.
• Found in vitamin B12.
Phosphorus (P)
• Like nitrogen, phosphorus (P) is an essential part of the process of photosynthesis.
• Involved in the formation of all oils, sugars, starches, etc.
• Helps with the transformation of solar energy into chemical energy; proper plant maturation; withstanding stress.
• Effects rapid growth.
• Encourages blooming and root growth.
• Phosphorus often comes from fertilizer, bone meal, and superphosphate.
Potassium (K)
• Potassium is absorbed by plants in larger amounts than any other mineral element except nitrogen and, in some cases, calcium.
• Helps in the building of protein, photosynthesis, fruit quality and reduction of diseases.
• Potassium is supplied to plants by soil minerals, organic materials, and fertilizer.
Calcium (Ca)
• Calcium, an essential part of plant cell wall structure, provides for normal transport and retention of other elements as well as strength in the plant. It is also thought to counteract the effect of alkali salts and organic acids within a plant.
• Sources of calcium are dolomitic lime, gypsum, and superphosphate.
Magnesium (Mg)
• Magnesium is part of the chlorophyll in all green plants and essential for photosynthesis. It also helps activate many plant enzymes needed for growth.
• Soil minerals, organic material, fertilizers, and dolomitic limestone are sources of magnesium for plants.
Sulfur (S)
• Essential plant food for production of protein.
• Promotes activity and development of enzymes and vitamins.
• Helps in chlorophyll formation.
• Improves root growth and seed production.
• Helps with vigorous plant growth and resistance to cold.
• Sulfur may be supplied to the soil from rainwater. It is also added in some fertilizers as an impurity, especially the lower grade fertilizers. The use of gypsum also increases soil sulfur levels.
Micronutrients
Boron (B)
• Helps in the use of nutrients and regulates other nutrients.
• Aids production of sugar and carbohydrates.
• Essential to actively growing tissue in new growth.
• Necessary for pollen viability and good seed set.
• Essential for seed and fruit development.
Copper (Cu)
• Important for reproductive growth.
• Aids in root metabolism and helps in the utilization of proteins.
• Important in photosynthesis, protein and carbohydrate metabolisms and nitrogen fixation.
Chloride (Cl)
• Aids plant metabolism.
• Chloride is found in the soil.
Iron (Fe)
• Essential for formation of chlorophyll.
• Sources of iron are the soil, iron sulfate, iron chelate.
Manganese (Mn)
• Functions with enzyme systems involved in breakdown of carbohydrates, nitrogen metabolism and protein production.
• Soil is a source of manganese.
Molybdenum (Mo)
• Essential for nitrogen fixation by nodule bacteria in legumes and for nitrogen conversion to amine form and for nitrogen assimilation.
• Soil is a source of molybdenum.
Zinc (Zn)
• Essential for the transformation of carbohydrates.
• Regulates consumption of sugars.
• Part of the enzyme systems which regulate plant growth.
• Affects plant maturity.
• Sources of zinc are soil, zinc oxide, zinc sulfate, zinc chelate.
Cobalt (Co)
• Essential for nitrogen fixation.
• Found in vitamin B12.