CALCIUM

Source of calcium

Calcium
displaces Sodium and releases nutrients

Calcium is a mineral nutrient classified as a secondary macronutrient. This category differentiates it from the primary macronutrients (Nitrogen, Phosphorus and Potassium) because it is required by plants in smaller quantities than these, but its deficiency limits plants growth. The calcium uptake by the plant is passive and does not require energy input.

Functions of Calcium

  • Promotes plant cell elongation
  • Takes part in stomatal regulation
  • Strengthens cell wall structure
  • Helps in protecting the plant against heat stress
  • Helps in protecting the plant against diseases
  • Improves callus deposition
  • Improves the organoleptic properties of the fruit and its shelf-life (post-harvest life)

Calcium availability

Although calcium is present in the soil it may not be available to plants due to different factors:

  • Soil pH: Calcium availability is only optimal between 7-8.5. Above or below these levels can precipitate in salts form, which can not be uptaken by plants.
  • Cation Exchange Capacity: The CEC measures the amount of ions a soil can hold. A lower CEC indicates a lower capacity of the soil to absorb and hold calcium.
  • Presence of competing  Ions: Positively charged ions such as Sodium or Magnesium might decrease Calcium uptake by plants.