Which nutrient is required for plant growth but is considered a micronutrient?

Boron is recognized as a micronutrient essential for plant growth. Micronutrients, in contrast to macronutrients, are required in smaller quantities, yet they play critical roles in various physiological processes within plants. Boron is particularly important in cell wall formation and the regulation of various metabolic functions, including the transportation of other nutrients within the plant. It contributes to crucial processes such as pollen formation and seed development, which directly impact plant reproductive success.

In contrast, phosphorus, calcium, and nitrogen are classified as macronutrients, as they are needed in larger amounts for plant growth and development. Phosphorus is vital for energy transfer and photosynthesis, calcium is essential for structural integrity and cell division, and nitrogen is important for amino acid synthesis and is a key component of chlorophyll. Each of these macronutrients supports various functions that are crucial for healthy plant development, but they are not categorized as micronutrients due to their higher required quantities.