To understand fertilizer and what it does, you have to know the roles that plant nutrients play in a plant’s growth and development.
Below is a list of primary and secondary nutrients required by most plants. Required amounts differ from plant to plant. Plants need nitrogen, phosphorus, and potassium in the largest amounts.
Primary Nutrients
Nitrogen (N)
An essential component of chlorophyll, hormones, amino acids, and important proteins, including enzymes and vitamins.
- Produces lush green growth.
- Increases protein content and plant vigor.
- Helps assimilate phosphorus, potash, and other plant foods.
Phosphorous (P)
Found in nucleoproteins and in lipoids, or phosphatized fats. Essential to carbohydrate transformations and respiration. Involved in high energy bonding.
- Stimulates early stem and foliage growth and hardy root formation.
- Hastens maturity.
- Promotes colorful flowers, healthy fruit and seen formation.
Potassium (K)
Not directly incorporated into organic compounds produced by plants but is a catalyst in converting starch to sugar. Essential to photosynthesis and cambial activity.
- Gives strength and stability to the plant
- Helps plants resist disease and regulates plant metabolism
- Helps plants resist cold and other adverse conditions
Secondary Nutrients
Boron (B)
Increases mobility of sugars and calcium. Important in cell division and protein synthesis. Essential to pollination. Affects flower formation, fruit set, and seed production.
Calcium (Ca)
Often the limiting factor in cell wall formation; indirectly involved with cell division.
Copper (Cu)
Catalyzes certain reactions in respiration. Component of some enzymes. Only molybdenum is required in smaller amounts.
Iron (Fe)
Essential to production of chlorophyll, although not a component of it. Carries electrons in certain functions. Component of certain enzymes and other proteins. Not readily mobile within the plant.
Magnesium (Mg)
The metallic component of chlorophyll. Catalyzes certain reactions and is readily mobile within plants.
Manganese (Mn)
Required in respiratory reactions and in the production of riboflavin and ascorbic acid. Essential to the reduction of carbon dioxide in photosynthesis.
Molybdenum (Mb)
Required in the smallest amounts of the essential nutrients (less than .05 ppm). Important in protein synthesis. Component of certain enzymes. Involved in nitrogen fixation, as in the nodules on the roots of legumes.
Sulfur (S)
Component of amino acids and proteins. Functions in the formation of chlorophyll.
Zinc (Zn)
Required in the production of growth-regulating substances (hormones). Catalyst in other reactions. Important in the formation of chlorophyll and in photosynthesis.
Chlorine (Cl)
Essential for the photosynthetic reactions in which water is split and oxygen is released (the mechanism is not fully understood). Symptoms of deficiencies: wilting leaves, becoming chlorotic and frequently turning bronze. Roots remain stunted.
Sodium (Na)
May be essential for some blue-green algae.
Silicon (Si)
Essential for diatoms (unicellular marine algae). May be required by some grasses (silicon is very abundant in grasses).
Cobalt (Co)
Required by some blue-green algae, at least those capable of atmospheric nitrogen fixation.
Soil acidity is measured by indications of pH points and several plant nutrient elements. There’s an optimum range of pH points for each nutrient. A soil pH above or below this optimum range can tie up certain nutrient elements, making them unavailable for your plants.
A pH test will tell you if you’re having nutrient problems. Our Anawalt Garden Center professionals can then guide you to the correct fertilizers for your situation.