Symptom differential
Lower-Leaf Yellowing
Yellowing that begins on older or lower leaves is a location pattern, not a diagnosis. It can reflect normal senescence, mobile-nutrient limitations, root stress, irrigation problems, salinity, or reduced light exposure.
Pattern questions
- Does yellowing begin uniformly or between veins?
- Is it limited to heavily shaded lower leaves or progressing upward?
- Are roots healthy and actively growing?
- Did irrigation, feed strength, pH, or environmental demand change recently?
Plausible cause categories
- Developmental senescence
- Root-zone oxygen or irrigation stress
- Mobile nutrient availability
- Salinity or root-zone chemistry
- Low-light leaf retirement
- Systemic disease or other whole-plant stress
Discriminating checks
- Inspect roots and substrate moisture
- Measure pH and EC using a consistent method
- Compare shaded and well-lit lower leaves
- Track whether new symptoms continue after root-zone conditions are corrected
Red flags
- Rapid whole-plant decline
- Wilting despite wet media
- Root sloughing or loss of fine roots
- Unusual one-sided or branch-specific progression
Visual study guide
- Old-versus-new leaf locator
- Uniform-versus-interveinal yellowing
- Shaded senescence comparison
- Root-context panel