| Mineral* | Functions | Deficiency | Excess |
Boron
| Micronutrient. Important for phloem transport and cell elongation. Aids production of sugars. Essential for fruit & seed development. | Growing tips become deformed or die, also leaf discolouration. | Leaf tips yellow & die. Leaves look scorched & fall. |
Calcium
| Secondary macronutrient. Many functions including structural integrity of cells & growing tips. | Reduced growth, deformation or death of growing tips. Poor fruit development. | May cause deficiency in either magnesium or potassium. |
| Carbon | From CO2 in air, essential to build sugars. | N/A | N/A |
Chlorine
| Micronutrient. Important in fluid balance & in breaking down water for photosynthesis. | Club roots. Wilted leaves becoming bronze, chlorotic then dying. | Salt injury causing leaf burn. |
Copper
| Micronutrient. Transition metal. Important in electron transport & reproductive growth. Aids in root metabolism and helps in the utilization of proteins. | Similar to Iron deficiency if soil acidic. | May cause distortion of new growth. Can occur in peat potting composts. |
| Hydrogen | From H2O, essential to build sugars. | N/A | N/A |
| Iron | Micronutrient. Transition metal. Important for enzyme synthesis & function. Electron transfer processes and chlorophyll synthesis. | Chlorosis. Yellow/white interveinal areas on young upper leaves leading to areas of leaf death. | May cause leaf bronzing with tiny brown spots. |
Magnesium
| Secondary macronutrient. This is an essential part of the chlorophyll molecule. Vital in photosynthesis and respiration. | Chlorosis, leaves appearing pale green or yellow. Yellowing between leaf veins spreading to younger leaves. poor fruit development and low yield. | Excess rare as well tolerated. Too much will suppress Calcium & Potassium & reduce growth. |
Manganese
| Micronutrient. Essential in photosynthesis & respiration including enzyme systems breakdown of carbohydrates. | Interveinal Chlorosis, yellowing or mottled young upper leaves. followed by brown spots giving a chequered red effect. | Reduced growth. Older leaves with brown spots surrounded by a chlorotic ring.
Looks like Iron deficiency. Can occur in acid soils. |
Molybdenum
| Micronutrient. Essential component of enzymes for nitrogen fixing. | Interveinal Chlorosis on older leaves which may distort. | N/A |
Nickel
| Micronutrient. Found in seeds and fruit. Needed to help form urease to break down urea nitrogen for plant use. Involved in the iron uptake from the soil. | Decreased iron utilization. | Chlorosis and necrotic leaf margins. |
| Nitrogen | Primary macronutrient. Needed for photosynthesis, growth & respiration. It is a constituent of DNA, RNA & amino acids which are used to build protein molecules. Nitrogen is inert & has to be incorporated into the plant by nitrogen-fixing bacteria in their root nodes. | Pale & lower leaves yellow or dying. Light green to yellow appearance of leaves, especially older leaves; stunted growth poor fruit development. | Dark green over vigorous foliage which is susceptible to disease & insect attack & will not overwinter well. Poor fruit & seeds. |
| Oxygen | O2, H2O. Essential for photosynthesis of sugar molecules. | N/A | N/A |
Phosphorus
| Primary macronutrient. Essential for reproduction & photosynthesis & involved in energy transfer & formation of oils, sugars & starches. Helps maturation, blooming & root growth. | Slow development, poor growth, flowering and fruiting. Leaves may appear purple. | May cause micronutrient deficiencies, especially iron or zinc. |
Potassium
| Primary Macronutrient. Activates many enzymes, encourages flowering & important in osmosis (fluid balance). Second to nitrogen in absorption for most plants. Builds disease resistance, improves fruit quality. | Older leaves yellowing around edges & then dying. Poor growth & vulnerable to disease. In Passiflora few or no flowers & poor fruiting & poor heat tolerance. | May cause deficiencies of calcium & magnesium. |
Sulphur
| Secondary macronutrient. Constituent of some amino acids. Enzyme cofactor and constituent. Improves root growth & seed production. Electron transfer processes and chlorophyll synthesis. Cold resistance. | Yellowing of young upper leaves spreading to whole plant. Occurs on new growth initially. | May cause early leaf drop. |
Zinc
| Micronutrient. Enzyme cofactor, growth hormone synthesis. Transformation of carbohydrates & sugar consumption. | Interveinal chlorosis/yellowing on young leaves, reduced leaf size. Rosetting. | May cause iron deficiency. |
Plant nutrients
