What is made here
Wine colours
Colours the rules allow. Pick a colour to filter the rules and grapes below.
Where it is
Roero in Italy
- Latitude
- 44.7°–44.9° N
- Vineyard altitude
- 196 m to 290 m
- Production zone
- 25,871 ha
Lies within
Nebbiolo d'Alba, Barbera d'Alba, Alba, Langhe, Piemonte
Worked out from the boundaries (smallest container first). They follow whole communes, so a neighbour sharing a commune can show up here too.
Boundary drawn from whole communes, so it is a little larger than the legal zone. Boundary: Eurac Research PDO inventory (CC0). Country outlines: Natural Earth. Dots on the zone map are the vineyard points used for climate.
Showing every colour The colour filter changes the rules and grapes. Climate, vintages and soils describe the vineyards, so they stay the same.
01 · What the law says
The rules
Limits on grapes, yields, ripeness and ageing that every wine labelled Roero must meet.
Blend rules
Roero
- ≥ 95% Nebbiolo · Main grape
- ≤ 5% other non-aromatic red grapes suitable in Piemonte · Others allowed
At least 20 months' ageing; release from 1 July of the second year after the harvest.
Blend rules
Roero Arneis
- ≥ 95% Arneis · Main grape
- ≤ 5% other non-aromatic white grapes suitable in Piemonte · Others allowed
Blend rules
Roero Arneis Spumante
- ≥ 95% Arneis · Main grape
- ≤ 5% other non-aromatic white grapes suitable in Piemonte · Others allowed
Blend rules
Roero riserva
- ≥ 95% Nebbiolo · Main grape
- ≤ 5% other non-aromatic red grapes suitable in Piemonte · Others allowed
At least 32 months' ageing; release from 1 July of the third year after the harvest.
Blend rules
Roero Arneis riserva
- ≥ 95% Arneis · Main grape
- ≤ 5% other non-aromatic white grapes suitable in Piemonte · Others allowed
At least 16 months' ageing; release from 1 March of the second year after the harvest.
Other varieties allowed
Besides the main grapes, the rules allow these varieties in some wines. Grape names link where a profile exists.
47 varieties · Roero, Roero riserva, Roero Arneis riserva
Albarossa, Ancellotta, Avana', Avarengo, Barbera, Becuet, Bonarda, Brachetto, Bragat Rosa, Cabernet Franc, Cabernet Sauvignon, Chatus, Ciliegiolo, Cornarea, Croatina, Dolcetto, Doux d'Henry, Durasa, Freisa, Gamay, Gamba Rossa, Grignolino, Lambrusca di Alessandria, Malvasia Nera Lunga, Malvasia di Casorzo, Malvasia di Schierano, Merlot, Montanera, Moscato Nero di Acqui, Ner d'Ala, Neretta Cuneese, Neretto di Bairo, Passau, Pelaverga, Pelaverga Piccolo, Petit Verdot, Pinot Noir, Plassa, Quagliano, Ruche', Sangiovese, Slarina, Syrah, Teroldego, Uva Rara, Uvalino, Vespolina
19 varieties · Roero Arneis, Roero Arneis Spumante
Baratuciat, Barbera Bianca, Bussanello, Cortese, Erbaluce, Favorita, Malvasia Moscata, Manzoni Bianco, Muller Thurgau, Muscat Blanc A Petits Grains, Nascetta, Pinot Blanc, Riesling, Rossese Bianco, Sauvignon Blanc, Sylvaner, Timorasso, Viognier, Welschriesling
In the vineyard and cellar: rules for every wine
3,500
Vines per hectare, minimum
No forcing
Forcing the vines is prohibited
Cellar
Where the wine must be made
Within the production zone
Allowed
Enrichment (chaptalisation)
02 · Climate fingerprint
The climate
The growing season averages 18.1 °C, warm on Gregory Jones's scale, with 1,743 growing degree days (Winkler III).
The average year 1991–2020, vineyards at about 260 m
Monthly mean, °CRain, mmGrowing season
- Growing-season temperature
- 18.1 °C
- Warm · 17–19 °C (Jones)
- Growing degree days
- 1,743
- Region III: 1,667–1,943 degree days
- Growing-season rain
- 549 mm
- Of 926 mm a year
- Harvest rain
- 182 mm
- September–October
Copernicus ERA5-Land monthly averages at 5 vineyard points (Vineyard point 1, 222 m; Vineyard point 2, 261 m; Vineyard point 3, 395 m; Vineyard point 4, 181 m; Vineyard point 5, 239 m), moved to each point's height from the model's terrain. Indices that need daily data are not captured yet. How the climate figures are made.
Lower confidence:Monthly reanalysis in moderately complex terrain; not yet checked against a weather station.
Closest climates in the database
Picked by the data, not by hand: the profiles nearest on season warmth (counted twice), degree days, rain, ripening-month nights and day–night range. Neighbours within 30 km are left out, as they share the same weather.
1. Colli TortonesiVery similarCompared with Roero: same season warmth, similar rain.
2. Dolcetto di Ovada SuperioreVery similarCompared with Roero: same season warmth, similar rain.
3. GaviVery similarCompared with Roero: same season warmth, similar rain.
Growing-season temperature
Growing degree days
Growing-season rain
03 · Year by year
35 vintages
Each column is one growing season: heat above or below the 1991–2020 average, and rain at harvest. Pick a year for the details.
Warmer than averageCooler than averageHarvest rain (Sep–Oct)Average harvest rain, 182 mm
2025
- Growing-season temp.
- Growing degree days
- Harvest rain
- Growing-season rain
- September nights
- Hot days and frosts
Seasons are labelled by harvest year (April–October). Year-to-year changes from ERA5-Land; tested against station records in Alto Adige (r = 0.94 for season temperature at Bolzano). Rain varies more locally, so treat single-season rain with some caution. Vintage ratings, harvest dates and frost or hail events have places in the data model but are not loaded yet.
04 · Where the numbers come from
Sources
- A geospatial inventory of regulatory information for wine protected designations of origin in Europe · Candiago et al., Scientific Data 9, 394 (2022); Eurac Research · CC0
- Quality wines in Italy and France: a dataset of PDO specifications · figshare 25393261 · CC BY 4.0
- ERA5-Land monthly averaged data (reanalysis-era5-land-monthly-means) · Copernicus Climate Change Service (C3S), Climate Data Store · CC BY 4.0 (Copernicus licence)
- OpenStreetMap vineyard areas (landuse=vineyard), from Geofabrik country extracts · OpenStreetMap contributors · ODbL 1.0
- Copernicus DEM GLO-90 (AWS open data tiles) · European Space Agency / Copernicus · Copernicus DEM licence
- Disciplinare di produzione: Roero (version published by MASAF up to May 2023, via the Internet Archive; later amendments not yet included) · Ministero dell'agricoltura, della sovranità alimentare e delle foreste (MASAF) · Official act
- Appellation nesting worked out from boundaries (pipeline/build_nesting.py) · Vinous, from the Eurac PDO boundaries · CC0 (source data)
- Climate profiles calculated by Vinous: method
Still to check (3)
- Generated from EU reference data: check against the current product specification.
- From the specification: DOCG; white wines may be labelled 'Roero' or 'Roero Arneis'. White Roero with an additional geographical mention needs 4 months' ageing and release from 1 March after the harvest. The spumante may range from brut nature to dolce and its production method is not specified. Max UGA yields shown are the 'vigna' yields from the seventh year.
- National tier (DOC/DOCG) not captured yet; rules extracted from the specification text.