Citrus
BORON
Young leaves show small water-soaked spots or flecks that become translucent as the leaves mature.
CALCIUM
Fading of chlorophyll along the leaf margins and between the main veins. Small necrotic, dead spots.
COPPER
Formation of unusually vigorous large dark green foliage with a “bowing up” of the midrib.
IRON
Symptoms occur on young leaves, which appear light yellowish to white, with the veins greener.
MAGNESIUM
Symptoms occur on mature leaves during the summer. Yellow colouring near the base along the midribs.
MAGNESIUM
Deficiency leads to a chlorosis in the interveinal tissue of leaves, but the veins remain dark green
NITROGEN
Deficiency first appears on older leaves. Symptoms are light yellowish-green leaves.
PHOSPHORUS
Phosphorus moves from older to younger tissues. Symptoms appear on older leaves, turning purple.
POTASSIUM
Deficiency may occur on acid sandy soils. Deficient plants show dieback of cells and tissue.
SULPHUR
Symptoms resemble those of N, but first appear on new leaves. Plants are stunted and pale green.
ZINC
Deficiency: Irregular green bands along the midrib on a background of light yellow to almost white.