Gadenin日本語Get the appCheck these first
- What colour are the spots, and do they have a yellow halo?
- Are there concentric rings or a mosaic pattern?
- Are the spots only on leaves, or also on stems and fruit?
Most likely causes
From the pests and diseases recorded for this plant, the ones whose symptoms match, most serious first. Symptoms alone rarely confirm a cause, so use the linked page to check the signs and treatment.
Downy Mildew
Pale yellow to yellow-brown angular lesions form on the upper leaf surface with a gray-purple mold in the matching spot underneath. Lesions merge, the leaves die back and the plant declines early.
How to identify and treat: Downy MildewBacterial Spot
Small water-soaked spots appear on the leaves, later turning brown with yellowing around them. Fruit develops water-soaked or scabby spots from which rot spreads.
General description; not specific to this plant.
How to identify and treat: Bacterial SpotPowdery Mildew
White patches appear scattered on the upper leaf surface at first, then the whole leaf is coated in a white powder. Leaves later yellow, brown and die back, and reduced photosynthesis cuts growth and yield.
General description; not specific to this plant.
How to identify and treat: Powdery MildewOther possible causes
- Gray Mold — Water-soaked brown lesions form on flowers, fruit and leaves, densely covered by a fuzzy g…
- Rust — Small raised orange-yellow to red-brown pustules form on both leaf surfaces, then rupture …
- Black Spot — On roses, dark brown lesions with radiating edges form on the leaves, which yellow around …
- Brown Leaf Spot — Small light brown to gray-brown spots form on the leaves and enlarge into irregular lesion…
- Ring Rot — The bark of branches and trunk becomes rough and warty, serving as the inoculum source. Fr…
- Brown Rot — Blossoms brown and die, and round brown lesions on fruit expand rapidly. Grayish white pow…
Other symptoms on this plant
What other growers did about it
A page like this one can tell you what grape leaf spots is and what to try. What it cannot tell you is what actually happened to someone who had it on the same plant, at the same point in the season, and what they did next.
Gadenin is a free garden journal built around that. You photograph the plant, tag what you are seeing, and the entries line up by date for each plant you grow.
- Tag the problem and the app tells you how many other growers have logged the same thing on the same plant.
- Growers who make their records public can be followed, so you can read what they did and how it turned out.
- Next season your own entries come back at the same point in the year, so you check the plant before it starts.
Free on iPhone. Recording, tagging and reading public records cost nothing.