Wine Grape - Discolouration
Symptoms
Starting on the tips grapes turn brown and dry out.
Reasons
Calcium deficiency
Wine Grape - Discolouration
Symptoms
Low calcium concentrations produce brown discoloration and rotting starting on the tips of grapes. Subsequently grapes dry out.
Reasons
Calcium deficiency (upper row)
Calcium deficiency made worse by
- Acidic soils
- Sandy or light soils (leaching)
- Acid peat soils
- Soils rich in sodium
- Soils rich in aluminium
- Drought conditions
- Fruit high in nitrogen or potassium
- Large fruit
Calcium is important for
- Improved berry quality
- Reduction of grape stalk necrosis
- Improved berry firmness and storage potential
