Why do plants need calcium?

Question

Why do plants need calcium?

Answer 1

Calcium is an essential plant nutrient. It is required for various structural roles in the cell wall and membranes, it is a counter-cation for inorganic and organic anions in the vacuole, and the cytosolic Ca2+ concentration ([Ca2+]cyt) is an obligate intracellular messenger coordinating responses to numerous developmental cues and environmental challenges.

Answer 2

Tomatoes develop a black mushy spot on the bottom if the soil is low in calcium , common in the sandy area of Florida I live in.