Variety Guru Gary

Plant Nutrients

PRIMARY PLANT FOOD ELEMENTS

ELEMENT FUNCTION
IN PLANT
DEFICIENCY
SYMPTOMS
EXCESS
SYMPTOMS
BEST
pH RANGE
SOURCE
Nitrogen Stimulates growth. Light green to yellow leaves.
Stunted growth.
Dark green, soft grown.
Retarded maturity.
Loss of buds or fruit
5.5-7.0 Organics
Synthetics
Urea
Ammonia
Nitrates
Phosphorus In enzymes hastens maturity.
Aids respiration.
Required in all cells.
Red or purple leaves.
Cell division retardation.
Tie up of other
essential elements.
5.5-7.0 Superphosphate
Potash Translocation of
materials in plants.
Regulates
photosynthesis.
Regulates formation of starch.
Reduced vigor.
Susceptibility to
diseases.
Thin skin and small fruit.
Coarse, poor
colored fruit.
Reduced absorption
of Mg and Ca.
5.5-7.0 Sulphate of Potash

SECONDARY PLANT FOOD ELEMENTS

Magnesium Aids photosynthesis.
Key element in chlorophyl.
Loss of yield.
Chlorosis of old leaves.
Reduced absorption of Ca and K. 5.5-6.5 Magnesium
Sulphate
Dolomite
Manganese In enzyme system. Mottled chlorosis of leaves. Stunted growth. Small dead areas in the leaves with yellow borders around them. 5.0-5.5 Manganese Sulphate
Copper Enzyme activator Multiple budding.
Gum pockets.
Prevents the uptake of Iron.
Causing stunting of roots.
5.5-6.5 Copper Sulphate
Neutral Copper

MICRO ELEMENTS

Zinc Aids in cell division.
In enzymes and auxins
Small, thin, yellow leaves.
Low yields.
None known. 5.0-5.5 Zinc Sulphate
Iron A catalyst. In the enzyme system. Hemoglobin in legumes. Yellowing of leaves, the veins remaining green. None known. 5.5-6.0 Iron sulphate
Chelated Iron
Sulphur Helps to build proteins. Looks like Nitrogen deficiency. Sulpher burn from too low pH. 5.5-8.0 Sulpher Superphosphate
Calcium Part of cell walls.
Part of enzymes.
Stops growing point of plants. Reduces the intake of K and Mg. 5.5-8.0 Lime Gypsum
Molybderium Helps in the utilization of N. Symptoms in plants vary greatly.   6.5-8.0 Sodium Molybdate
Boron Affects absorption of other elements.
Affects germination of pollen tube.
Small leaves, corkiness. Multiple buds. Leaves turn yellowish red. 5.5-6.5 Borax

ELEMENTS FROM AIR AND WATER

Carbon Keystone of all organic substances None known. None known.   Air.
Oxygen Respiration White areas of leaf veins High Nitrates. None known.   Air and Water.
Hydrogen Necessary in all plant functions. Wilting Drowning.   Water