Cucumber · Symptom guide
Powdery mildew on cucumber
White marks on cucumber leaves in a garden bed are a look-and-compare job. Cited sheets list powdery growth as observations, not a ranked or confirmed cause. This page does not diagnose.
Cited observations are comparisons—not a confirmed diagnosis. Check the cited sources and local requirements before taking action.
Save this bed. See it coming next year.
Your checks stay in the Field Book so next season is not a guess.
Illustrative photograph — not identification proof.
Look
Compare the plant in front of you with the cited notes after Other causes. Leaf marks alone do not name a cause on this page.
Other causes
Growing notes live on how to grow cucumber. Garden-wide looks live on garden pests.
What the sources say — at a glance
One source per card. Facts are not averaged.
UMN Extension (Minnesota)
Powdery white spots on leaves and vines.
Details and limits (2)
Look
UMN Extension (Minnesota): powdery mildew is a fungal disease that causes powdery white spots to form on leaves and vines. Observation. Cucumber as named.
Limit
Minnesota growing-cucumbers sheet. Observation only — not a diagnosis.
Maryland Extension (Maryland)
White powdery coating. Cucumber named.
Details and limits (2)
Look
Maryland Extension (Maryland): powdery mildew grows as a white powdery coating over the surfaces of leaves. Cucumber named on that sheet. Observation.
Limit
Maryland powdery-mildew vegetables sheet. Cucumber named — not a diagnosis.
Sources differ
Make it yours
Save the bed in the Field Book so next season is not a guess.
How we know — methodology. Ranges and assertions are cited per source, not blended.