Diagnostic Guide
Why do my plant's leaves have tiny light spots or webbing?
Check the undersides of leaves and tap a leaf over white paper to look for tiny moving specks before treating anything else.
Last reviewed: August 6, 2026 · Sources: University of California IPM
Start with the visible pattern
| What you see | Most likely cause | Check first |
|---|---|---|
| Fine light stippling with visible webbing | Spider mites | Tap a leaf over white paper to check for moving specks |
Hold a plain white sheet of paper under a leaf and tap it firmly. Tiny specks that start moving on the paper confirm spider mites.
Simple checks before you buy anything
Most garden problems have more than one possible cause. Start with the simplest explanation.
- Inspect the undersides of leaves and any webbing between leaves or stems.
- Isolate the plant from others while you confirm and treat, since mites spread easily.
- Increase humidity around the plant, since mites thrive in dry air.
Most likely causes to check first
Spider mites
Confidence: 85%Spider mites are tiny sap-feeding pests that thrive in warm, dry indoor air and cause fine light-colored stippling on leaves, sometimes with visible webbing in heavy infestations.
- Hold a white sheet of paper under a leaf and tap it; moving specks confirm mites rather than a nutrient issue.
- Check the undersides of leaves and any fine webbing between leaves or stems.
- Note whether the plant has been in an especially warm, dry spot recently.
Reference material used on this page
University of California IPM
Powdery mildew identification and control
Publication date: 2025
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