Soil fertility is the ability of soil to supply essential nutrients to crops in adequate amounts for healthy growth and optimum yield.
There are various methods to evaluate soil fertility. Three important ones are:
1. Soil testing: This is the most scientific method to assess the nutrient status of soil.
Soil samples are collected from different parts of a field and analyzed in a laboratory for macro and micronutrients, pH, and organic carbon.
Based on the results, farmers receive fertilizer recommendations to correct deficiencies and maintain soil health.
2. Observation of crop growth: Farmers and extension workers observe visual symptoms of nutrient deficiencies in crops.
Yellowing of leaves, stunted growth, poor flowering, or fruiting are signs that indicate specific nutrient problems.
Although this method is simple, it requires good knowledge to correctly identify deficiency symptoms.
3. Plant tissue analysis: This involves sampling plant parts like leaves or stems during the growing season to measure nutrient content.
It helps detect hidden hunger — a condition where crops appear normal but yield is reduced due to sub-optimal nutrient levels.
Tissue analysis complements soil testing and ensures timely corrective action through foliar sprays or top dressing.
Combining these methods provides a complete picture of soil fertility and helps farmers make informed nutrient management decisions.