Paso Robles AVA

11 Viticultural Areas

American Viticultural Area labeling helps tell a story of a region and guide wine trade and enthusiasts in understanding growing conditions and potential expectations of a specific region. The 11 viticultural areas of Paso Robles demonstrate the diversity of Paso Robles Wine Country and provide information to consumers and trade about what is in the bottle, helping them make a better-informed buying decision.

As Jason Haas of Tablas Creek nicely summed it up in his September 28, 2013, blog post

Paso Robles was the largest un-subdivided AVA in California at approximately 614,000 acres. By contrast, the Napa Valley appellation (which includes sixteen AVA’s delineated within its bounds) is roughly one-third the area at 225,000 acres. Since the Paso Robles AVA was established in 1983, Paso Robles has grown to encompass 200+ wineries and 40,000 vineyard acres.  This vineyard acreage is spread over a sprawling district roughly 42 miles east to west and 32 miles north to south.  Average rainfall varies from more than 30 inches a year in extreme western sections to less than 10 inches in areas farther east.  Elevations range from 700 feet to more than 2400 feet.  Soils differ dramatically in different parts of the AVA, from the highly calcareous hills out near us to sand, loam and alluvial soils in the Estrella River basin.  The warmest parts of the AVA accumulate roughly 20% more heat (measured by growing degree days) than the coolest; the average year-to-date degree days in the Templeton Gap since 1997 is 2498, while in Shandon far out east it’s 2956.  This difference in temperatures is enough to make the cooler parts of the AVA a Winkler Region II in the commonly used scale of heat summation developed at UC Davis, while the warmest sections are a Winkler Region IV.

These 11 new AVA’s will be a powerful tool for wineries to explain why certain grapes are particularly well suited to certain parts of the appellation, and why some wines show the characteristics they do while other wines, from the same or similar grapes, show differently. Ultimately, the new AVA’s will allow these newly created sub-regions to develop identities for themselves with a clarity impossible in a single large AVA. Click here to view the final TTB ruling.

Viticultural Area                                                                                   ClimateAvg. Annual Rainfall (inch)                Diurnal Growing Season Temp. Change (°F)  TopographySoil
Paso Robles*Maritime climate becom-ing more continental to the east, with growing de-gree-day Regions II, III and IV.8 – 3020 – 50Salinas River and tributary valleys, alluvial terraces, and surrounding mountain slopes; 600 – 2,400+ feet.Soils both depositional and residual derived from sedi-mentary rock; moderate depth.
Adelaida DistrictRegion II–III transitional2530Santa Lucia Range high mountain slopes grading to foothills; 900 – 2200 feet.Shallow, bedrock residual soils and patchy colluvial hillside soils from middle member of Monterey For-mation and older rocks; largely calcareous soils.
Creston DistrictRegion III11.525Old erosional plateau at the base of the La Panza Range; alluvial terraces and fans of Huerhuero Creek; 1,000 – 2,000 feet.Old, well developed terrace and hillside soils; mix of granitic and sedimentary rocks.
El Pomar DistrictRegion II1520-25High, older terraces, fans, and hills; 740 – 1,600 feet.Quaternary alluvial soils, well developed loams to clay loams, some calcare-ous, with Monterey For-mation sand- stone and silt-stone at depth in some are-as.
Paso Robles Estrella DistrictRegion III12.5 – 15.535 – 40Rolling plains of Estrella River valley and terraces; 745 – 1819 feet.Quaternary alluvial soils of diverse ages across young-er to older terraces, deep to moderate depth, with rem-nant patches of older valley fill at highest elevations.
Paso Robles Geneseo DistrictRegion III – IV13 – 1420 – 25Upfaulted hills through old river terraces along Huerhuero–La Panza fault; 740 – 1,300 feet.Old alluvial terrace and re-sidual hillside soils of mod-erate depth with cementa-tion of the gravelly Paso Robles Formation and older granites.
Paso Robles Highlands DistrictRegion IV1250+Old Pliocene–Pleistocene erosional surface across the Simmler, Monterey and Paso Robles formations be-low the La Panza Range; 1,160 – 2,086 feet.Deep, sometimes cemented alluvial soils; old leached alkaline soils common, with younger sandy soils along active steams.
Paso Robles Willow Creek DistrictRegion II24 – 3020High elevation mountainous bedrock slopes across a more erodible member of the Monterey Formation; 960 – 1,900 feet.Mostly bedrock (residual) soils from the middle and lower members of the Mon-terey Formation, patches of alluvial soil along streams, largely calcareous, loams to clay loams.
San Juan CreekRegion III – IV transition10.435-40San Juan Creek younger river valleys with alluvial ter-races and fans as a tributary to the upper Estrella River; 980 – 1,600 feet.Well to moderately drained, deep alluvial soils, sandy loams to loams to clay loams on the highest, oldest terraces.
San Miguel DistrictRegion III11.430-35Footslope of Santa Lucia Range, with alluvial terraces of the Salinas and Estrella rivers and small recent allu-vial fans; 580 – 1,600 feet.Deep, alluvial sandy loams to loams to a few clay loams (some with clay pans) from the river bottoms up onto the higher terraces.
Santa Margarita RanchRegion II2925High, steep mountain slopes of ancient Salinas River and upper reaches of incised con- temporary Salinas Riv-er along the Rinconada Fault; 900 – 1,400 feet.Deep alluvial soils derived from many lithologies and varying in texture, with patchy residual soils on mountain slopes.
Templeton Gap DistrictRegion II2020Santa Lucia Range moun-tain slopes and broad alluvi-al terraces; elevations 700 – 1,800 feet.Broad alluvial terraces and fans of Paso Robles Creek and the Salinas River over bed- rock; alluvial soils of shallow to moderate depth and sandy to silty to clay loams; calcareous in places.

* The growing season referenced herein is from April 1 to October 31 in a calendar year

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