Visual diagnosis
Mobile nutrients (N, P, K, Mg) show symptoms on older leaves first as plant remobilizes them to new growth. Immobile nutrients (Ca, Fe, B) affect young tissue first.
Common deficiencies
- Nitrogen — general chlorosis, stunting
- Iron — interveinal chlorosis on young leaves
- Potassium — marginal necrosis, weak stems
- Calcium — blossom end rot in fruits, tip burn in lettuce
Confirmation
Tissue analysis in lab confirms visual diagnosis — soil tests alone may miss uptake issues (pH, root disease).