LESSON FIVE

Nutrients Requirements and Testing 5 -2

Nutrient 

Deficiency

Excess

Nitrogen

Older leaves turn chlorotic and may
eventually die. Plant is stunted
Foliage is light green.

Plant becomes over vigorous, leaves become very dark green.
Fruit clusters have excessive growth and fruit ripening is delayed.

Potassium

Older leaves appear chlorotic between veins, but veins remain green.
Leaf edges may burn or roll.

Uncommon to show toxicity.
Secondary manganese
deficiency may occur.

Phosphorous

Stem, leaf veins, petioles turn yellow, followed by reddish-purplish as
phosphorous is drawn from them
into the new growth. Seedlings may
develop slowly. Fruiting is poor.

No direct toxicity. Copper and zinc availability may be reduced.

Calcium

Plant is stunted. Young leaves turn
yellow. Blossoms die and fall off.
 Tomatoes may develop brown
  spots on the fruit.

 No direct toxicity.

Sulfur

Younger leaves become yellow with purpling at base. Older leaves turn light green.

Small leaves.

Iron

New growth pales, veins stay green. Blossoms drop off. Yellowing occurs between veins.

Very uncommon.

Magnesium

Older leaves curl and yellow areas
appear between veins. Young leaves curl and become brittle.

No direct toxicity.

Zinc

Leaves become chlorotic between
veins and often develop
necrotic spots.

Reduces availability of iron.

Molybdenum

Older leaves turn yellow and leaf margins curl.

 Rare. Tomato leaves may turn bright yellow.

Copper

Pale yellow. Leaves become spotted. Plant is stunted.

May reduce availability of iron.