Calcium deficiency first affects actively growing parts. It is especially recognized in fruit quality problems such as blossom end rot in tomatoes and peppers, or bitter pit in apples.

Typical symptoms:
• Deformed, curled, or dry-tipped young leaves.
• Necrosis on the edges and tips of new leaves.
• Deterioration of fine root and shoot growth.
• Appearance of dark, sunken spots on fruit (e.g., blossom end rot in tomatoes).
• Soft or watery texture on fruit and leaves.

As a non-mobile nutrient, calcium deficiency develops in a localized manner, primarily affecting growing organs, with a strong impact on production quality.

Developmental stages:
• Initial: mild deformations in young leaves and shoot tips.
• Intermediate stage: necrosis at leaf tips and flower abortion.
• Advanced: sunken spots on fruit, blossom end rot.
• Final: loss of commercial value of the crop and reduction in yield.