PLANT HEALTH
Something looks wrong with your plant?
Start with observations before reaching for a treatment. Yellowing, spots, wilting and slow growth can have different causes, even when two plants look similar.
A symptom checklist, not an automated diagnosis. A photograph alone cannot confirm a disease.
OBSERVE FIRST
Six things to check before treatment
- 1. Identify the plant: crop, variety if known, and growth stage.
- 2. Map the symptoms: older or new leaves, stem, fruit or the whole plant?
- 3. Inspect closely: spots, rings, mould, pests, curling or physical damage?
- 4. Check the soil: note moisture, drainage, watering and recent fertilizing.
- 5. Review the weather: frost, heat, rain and wind can affect appearance.
- 6. Record change: photograph it now and compare if symptoms spread.
Visible symptoms are a useful clue but do not always reveal root conditions or the full cause.
START WITH A SPECIFIC SYMPTOM
Yellow tomato leaves
Yellow foliage may involve normal ageing, shade, nutrients, water stress or disease. The location of yellowing and any distinct spots matter more than colour alone.
Read the tomato guide for a careful first assessment, without assuming a diagnosis from one symptom.
CHECK THE CONDITIONS
Don’t overlook water and light.
Soil and watering
Roots need water and air. Check root-zone moisture before adding more.
Light and placement
Limited sunlight can affect growth. Harsh weather can also damage exposed tissues.
WHEN TO ASK FOR HELP
Seek a qualified local diagnosis when needed.
For rapid decline, repeated unexplained wilting, spreading lesions or uncertain pest identification, consult a local Master Gardener program, horticultural extension service or diagnostic clinic. Share photographs and notes about growing conditions. Always follow local rules and product labels before using pesticides.
RELIABLE REFERENCES
Compare evidence, not guesses.
The University of Minnesota Extension symptom guide demonstrates several different causes of discoloured tomato leaves. Mississippi State University Extension covers other common tomato disorders.