An important means of managing the nutrient requirements of plants is
being able to recognise nutrient deficiencies and toxicity as early as
possible to minimize their impact on plants.
Deficiency - symptoms
Consult the experts when in doubt. The following is for guidance only.
Water problems caused by:
High conductivity, high salinity, low availability of water i.e.
drought conditions will cause the edges of the leaves to burn and in
severe cases leaves will drop from the plant. (The plant suffers
from thirst.)
pH problems:
Availability of nutrients for plants is affected by pH. If the pH
moves too far from the plants preferred range then there can be
nutrient deficiencies.
Potassium:
Lower leaves are mottled. Yellowing and death of tips and edges of
older leaves.
Nitrogen: deficient
Lower leaves mainly affected.
When severe, effects appear over whole plant while lower leaves go
dry
The plant is light in colour and weak and spindly.
Small leaves with the lower leaves light green.
Plant light green, lower leaves yellow, drying to light brown
colour, stalks short and slender if element is deficient in later
growth stages.
some plants ( strawberries ) show a reddening of the older leaves.
Nitrogen: to much ammonia
Too much N/NO3 - plants uncontrollably vigorous. Too much N/NH4
ammonia will cause damage to roots and collapse of plant
Phosphorous:
Leaves are unusually dark and may become purple. Lower leaves may
turn yellow between the veins. Plants are stunted
Calcium:
Tips of young leaves and growing points die. Blossom end rot of
tomatoes.
Magnesium:
Margins of lower leaves curl. Young leaves' veins yellow. Leaves
may redden.
Iron:
Younger leaves yellow between veins but yellowing spreads to whole
leaf and the leaves die from the edges.
Manganese:
Upper leaves become yellow between the veins and in severe cases
dead spots form. The veins remain green. Chequered effect on
young leaves.
