soil
Nutrient deficiency
Last reviewed 2026-10-04
A nutrient deficiency occurs when a plant cannot obtain enough of an element needed for normal growth. The cause may be too little nutrient in soil, unsuitable pH, damaged roots, excess water, salt injury, or another condition that prevents uptake. A leaf symptom alone is rarely enough to identify the deficiency.
What it means
Plants need macronutrients such as nitrogen, phosphorus, and potassium, along with calcium, magnesium, sulfur, and micronutrients. Nutrients move differently through a plant, so the age and pattern of affected leaves can provide clues. Soil and tissue tests are more reliable than color alone.
How it affects the garden
Check soil, irrigation, drainage, roots, and recent weather before adding fertilizer. Excess of one nutrient can interfere with another and damage plants. Correct pH only when a test supports it. Use the fertilizer calculator to convert a known rate, not to guess a diagnosis.
Example
Older leaves yellow while newer growth stays green. Nitrogen shortage is one possibility, but waterlogged roots, natural aging, or disease can create similar patterns.
Common confusion
A nutrient deficiency is not the same as a nutrient being absent. A nutrient may be present but unavailable because of pH, moisture, or root conditions.
Sources
University of Minnesota Extension explains soil testing and nutrient management.
