Why does your Citrus aurantiifolia have yellow leaves? Diagnose the cause and fix it with our step-by-step guide.
Nitrogen is a mobile nutrient in citrus; when lacking, the plant moves it from older leaves to new growth, causing uniform yellowing (chlorosis) of older foliage first.
Key limes are sensitive to 'wet feet'; saturated soil displaces oxygen, causing root suffocation which prevents nutrient uptake and leads to chlorosis.
If the soil pH is too high (alkaline), iron becomes chemically locked in the soil, making it unavailable to the lime tree despite being present.
Larvae of this pest tunnel through the leaves, creating serpentine tracks that can cause the leaf tissue to die and turn yellow or brown.
Your plant might also be experiencing one of these issues: