# Backyard Grapes

> A free, non-commercial, educational guide that helps home grape growers identify and treat the most common grapevine diseases, pests, and disorders.

The guide covers 39 problems. Each entry maps to the part(s) of the vine it affects (leaf, shoot, fruit, trunk, roots), lists identifying symptoms and easily-confused look-alikes, and groups treatment into cultural, organic, and chemical options. Images are used for non-commercial, educational purposes only.

## Fungal diseases

- [Anthracnose](https://backyardgrapes.com/diseases/anthracnose.md): Sunken spots with dark margins on shoots and berries — the classic "bird's-eye rot".
- [Armillaria root rot](https://backyardgrapes.com/diseases/armillaria-root-rot.md): A soilborne fungus that rots roots and crown, killing vines in a slowly widening patch.
- [Bitter rot](https://backyardgrapes.com/diseases/bitter-rot.md): A late-season berry rot that softens ripe fruit and leaves it bitter — often riding in behind other rots.
- [Black foot & Petri disease](https://backyardgrapes.com/diseases/black-foot.md): Soilborne trunk-disease fungi that rot the base and wood of young vines, causing them to fail in the first years.
- [Black rot](https://backyardgrapes.com/diseases/black-rot.md): Tan leaf spots ringed with black dots, and berries that shrivel into hard black mummies.
- [Botryosphaeria dieback](https://backyardgrapes.com/diseases/botryosphaeria-dieback.md): A trunk-disease complex that cankers cordons and kills spurs, closely mimicking Eutypa.
- [Botrytis bunch rot (grey mould)](https://backyardgrapes.com/diseases/botrytis-bunch-rot.md): Fuzzy grey mould that rots ripening clusters, especially after rain near harvest.
- [Downy mildew](https://backyardgrapes.com/diseases/downy-mildew.md): Yellow "oil spots" on top of the leaf with white fuzz underneath — loves wet, warm weather.
- [Esca (trunk disease)](https://backyardgrapes.com/diseases/esca.md): A chronic wood rot of older vines, showing as "tiger-stripe" leaves and sudden collapse.
- [Eutypa dieback](https://backyardgrapes.com/diseases/eutypa-dieback.md): A slow trunk disease ("dead arm") that stunts spring shoots and kills cordons one arm at a time.
- [Grape rust](https://backyardgrapes.com/diseases/grape-rust.md): Bright orange pustules that dust the underside of leaves, causing early leaf drop in warm regions.
- [Phomopsis cane & leaf spot](https://backyardgrapes.com/diseases/phomopsis.md): Black specks and cracked bark on the base of shoots, plus small spots on lower leaves.
- [Powdery mildew](https://backyardgrapes.com/diseases/powdery-mildew.md): A dusty white-grey coating on leaves and berries — the most common grape fungus almost everywhere.
- [Ripe rot](https://backyardgrapes.com/diseases/ripe-rot.md): Reddish-brown circular rot on ripening berries, often oozing salmon-pink spores.
- [Sour rot](https://backyardgrapes.com/diseases/sour-rot.md): Clusters that turn to vinegar-smelling mush late in the season, swarming with fruit flies.

## Bacterial diseases

- [Crown gall](https://backyardgrapes.com/diseases/crown-gall.md): Warty, tumour-like growths on the trunk near the soil line, often after winter injury.
- [Pierce's disease](https://backyardgrapes.com/diseases/pierces-disease.md): A bacterium spread by sharpshooter insects that clogs the vine's plumbing and kills it over 1–3 years.

## Viral diseases

- [Grapevine fanleaf virus](https://backyardgrapes.com/diseases/fanleaf-virus.md): A nematode-spread virus that deforms leaves into a fan shape and leaves the crop straggly.
- [Grapevine leafroll](https://backyardgrapes.com/diseases/leafroll-virus.md): Autumn leaves that roll downward and turn deep red or yellow while the veins stay green.
- [Grapevine red blotch](https://backyardgrapes.com/diseases/red-blotch.md): Red blotches on leaves that mimic leafroll but mainly delay ripening and lower sugar.

## Insect & mite pests

- [European grapevine moth](https://backyardgrapes.com/diseases/european-grapevine-moth.md): The main cluster caterpillar of European vineyards — eats flowers, then berries, inviting rot.
- [Grape berry moth](https://backyardgrapes.com/diseases/grape-berry-moth.md): Caterpillars that web and bore into berries, opening the door to bunch rots.
- [Grape erineum mite](https://backyardgrapes.com/diseases/grape-erineum-mite.md): A microscopic blister mite that raises fuzzy welts on leaves — alarming but rarely harmful.
- [Grape leafhopper](https://backyardgrapes.com/diseases/grape-leafhopper.md): Small hoppers whose feeding stipples leaves white; heavy numbers scorch the canopy.
- [Grape mealybug](https://backyardgrapes.com/diseases/grape-mealybug.md): Soft, waxy sap-suckers that foul clusters with honeydew — and spread leafroll virus.
- [Grape phylloxera](https://backyardgrapes.com/diseases/phylloxera.md): A tiny root-feeding aphid-like insect that devastates own-rooted European grapes.
- [Japanese beetle](https://backyardgrapes.com/diseases/japanese-beetle.md): Metallic beetles that skeletonise leaves, chewing the tissue between the veins into lace.
- [Root-knot nematode](https://backyardgrapes.com/diseases/root-knot-nematode.md): Microscopic soil roundworms that gall the roots and stunt vines, especially on sandy soils.
- [Spider mites](https://backyardgrapes.com/diseases/spider-mites.md): Tiny sap-sucking mites that stipple and bronze leaves in hot, dusty, dry conditions.
- [Spotted lanternfly](https://backyardgrapes.com/diseases/spotted-lanternfly.md): An invasive planthopper that swarms vines, sucking sap and coating them in sticky honeydew and sooty mould.

## Disorders (abiotic / non-living causes)

- [Boron deficiency](https://backyardgrapes.com/diseases/boron-deficiency.md): Poor fruit set with "hen and chicks" clusters and dying shoot tips — common on dry, sandy soils.
- [Herbicide drift](https://backyardgrapes.com/diseases/herbicide-drift.md): Distorted, cupped, fan-shaped new growth from weed-killer that drifted onto the vine — not a disease at all.
- [Iron deficiency](https://backyardgrapes.com/diseases/iron-deficiency.md): Yellowing of the youngest tip leaves with green veins — usually a high-pH soil problem, not a lack of iron.
- [Magnesium deficiency](https://backyardgrapes.com/diseases/magnesium-deficiency.md): Yellowing between the veins of older leaves while the veins stay green — one of the commonest grape disorders.
- [Nitrogen deficiency](https://backyardgrapes.com/diseases/nitrogen-deficiency.md): Uniformly pale, small leaves and weak growth from too little nitrogen — the vine simply lacks vigour.
- [Potassium deficiency](https://backyardgrapes.com/diseases/potassium-deficiency.md): Scorched, curling leaf margins on older leaves and poorly ripening fruit — a heavy-cropping vine's shortfall.
- [Sunburn & sunscald](https://backyardgrapes.com/diseases/sunburn.md): Heat and intense sun scorching exposed berries and leaves — often triggered by over-thinning the canopy.
- [Winter & frost injury](https://backyardgrapes.com/diseases/winter-injury.md): Cold damage that kills buds, splits bark, and kills trunks — a frequent look-alike for trunk disease.
- [Zinc deficiency](https://backyardgrapes.com/diseases/zinc-deficiency.md): Small "little leaf" growth and straggly, shot-berry clusters — a look-alike for fanleaf virus.

## More

- [All problems, filterable by type](https://backyardgrapes.com/diseases/)
- [Full text of every entry, for LLMs](https://backyardgrapes.com/llms-full.txt)
- [Licensing & image use](https://backyardgrapes.com/licensing/)