Local Terroir
Geological Influences
The San Joaquin Valley is a vast basin, formed more than 65 million years ago. It is bounded by the granitic Sierra Nevada mountains to the east and sedimentary Coast Ranges to the west. Erosion from both is the primary source of the valley’s soils.
Through the first 60 million years of existence, though, the basin was covered by water. Initially connected to the ocean, shifts in the land and a declining sea level eventually made the area an inland sea.
During this extended marine period, vigorous sea life resulted in rich, organic deposits, more than nine km (almost six miles) thick in some areas. Millions of years of heat and pressure turned those deposits into shale and oil. So, while the San Joaquin Valley is extremely important agriculturally, it has also accounted for the majority of California oil production.
Though not agriculturally significant, the San Andreas Fault has also played a role in the valley’s topography and geology. Originally a deep ocean trench, it became ground zero for tectonic plates shifting laterally and also for the subduction which formed the Coast Range. The southern end of the fault runs along the valley’s western edge.
Mountains/Rivers/Other Key Influences
Most winegrowing in the San Joaquin Valley takes place on the valley floor, with the influence of the mountains limited to soil generation and isolation from the ocean. Erosion from the mountain ranges provided most of the valley’s top soils. The Coastal Range shields most of the valley from the rain and temperature moderation Pacific Ocean breezes might otherwise contribute.
The San Joachin and Kings Rivers moderate temperatures somewhat, but only in vineyards which are very near.
Soil Diversity
Because the San Joaquin Valley is so large and has so many geological influences, its agricultural lands are a hodgepodge of soils. Please see the individual AVA sections for details.
Climate
The San Joaquin Valley climate is generally hot and arid with a very long growing season and moderate winters. Northern parts of the valley, especially Lodi, are close enough to the bay and ocean to have Mediterranean climates, the high and low temperatures moderated by the huge expanse of water. That moderation decreases steadily, moving south from Lodi to areas farther from the water and shielded from wind and rain by mountains. The valley’s southernmost area is desert.
With the shift in climate from north to south, optimal grape varieties vary too. Lodi is well-known for red wine varieties such as Zinfandel, Petite Sirah, and Cabernet Sauvignon, which like warm, sunny climates. However, the cool evenings provide favorable conditions for growing compelling, low-alcohol wines from Vermentino and Grenache Blanc. The hotter climate of the Tracy Hills AVA recommends robust black grapes such as Tempranillo and Touriga Nacional, rather than whites. And the hottest areas of the valley produce wonderful fortified wines.
Lodi AVA
- # AVAs
- 8 (Lodi, Mokelumne River, Jahant, Cosumnes River, Sloughhouse, Alta Mesa, Borden Ranch, Clements Hills)
- Year Established
- 1986 Lodi, 2006 Mokelumne River, 2006 Jahant, 2006 Cosumnes River, 2006 Sloughhouse, 2006 Alta Mesa, 2006 Borden Ranch, 2006 Clements Hills
- Number of Wineries
- 85
- Hectares/Acres Under Vine
- 40,469 hectares / 100,000 acres (20% of total area)
- Crush/Production
- 800,000 tons / 2,265,347,727 liters*
- Key Varieties (based on 2019 plantings)
- 71% Red; 29% White; Cabernet Sauvignon (23%), Zinfandel (16%), Chardonnay (15%), Merlot (10%), Pinot gris (8%), Petite Sirah (6%)
- Climate
- Mediterranean
- Key Soil Types
- Tokay series (fine sandy loam), San Joaquin series (shallow sandy clay loam), Redding series (gravelly clay)
Sub-AVA’s
Location/Geography
Central/northwestern edge of Lodi AVA; falling in both Sacramento and San Joaquin Counties 28,328 ha/70,000 acres, with over 4,856 ha/ 12,000 acres of planted grapes
Name Background
Borden Ranch founded in 1864, giving name to surrounding community
Topography/Elevation/Water Sources/Geographic Features
22-158 m/73- to 520-feet elevation; hilly, prairie mound topography, largely volcanic, rocky slopes with some alluvial stream deposits
Geology/Soil Composition
Redding series (rocky clay loam)
Climate
Mediterranean
Main Grape Varieties
Cabernet Sauvignon, Merlot, Malbec, Petit Verdot, Syrah, Petite Sirah, Primitivo/Zinfandel, Chardonnay, Pinot Grigio, Sauvignon Blanc, Verdejo, Verdelho, Garnacha Blanca
Location/Geography
South-central eastern edge Lodi AVA, falling in San Joaquin County
34,560 ha/ 85,400 acres, and the largest planting of wine grapes: 8,782 ha/21,700 acres
Name Background
Hamlet of Clements founded by Thomas Clements in 1857, giving name to surrounding community
Topography/Elevation/Water Sources/Geographic Features
30.5-137 m/100- to 450-feet elevation; rolling hills woodland environment with sandy alluvial fans in vicinity of Mokelumne River
Geology/Soil Composition
Redding series (rocky clay loam)
Climate
Mediterranean (widest diurnal swings in Lodi AVA)
Main Grape Varieties
Cabernet Sauvignon, Merlot, Petit Verdot, Malbec, Primitivo/Zinfandel, Barbera, Petite Sirah, Nebbiolo, Syrah, Mourvèdre, Grenache, Grenache Blanc, Albariño, Tempranillo, Graciano, Chardonnay, Sauvignon Blanc, Piquepoul.
Location/Geography
Northwest corner of Lodi AVA; mostly in Sacramento County
Currently 22,136 ha/54,700 acres, with the smallest amount of planted wine grapes (about 1,416 ha/3,500 acres) of Lodi’s seven sub-AVAs
Name Background
Cosumnes River watershed area
Topography/Elevation/Water Sources/Geographic Features
1.4-14.5 m/5- to 48-feet elevation; lower areas consist of alluvial floodplain, sloughs and wetlands; higher terrace areas with shallow clay hardpan
Proximity to Delta fog and near-sea level elevation make this one of Lodi’s cooler climate appellations
Geology/Soil Composition
San Joaquin series (shallow, sandy clay loam)
Climate
Mediterranean
Main Grape Varieties
Chardonnay, Sauvignon Blanc, Pinot Grigio, Vermentino, Cabernet Sauvignon, Merlot, Syrah
Location/Geography
West-central part of Lodi AVA, falling mostly in San Joaquin County
The smallest of Lodi’s seven AVAs — comprising 11,331 ha/28,000 acres, with 3,642 ha/9,000 acres planted
Name Background
Jahant family began farming in area in 1850s, lending name to several local landmarks and businesses
Topography/Elevation/Water Sources/Geographic Features
30.5-137 m/100- to 450-feet elevation; rolling hills woodland environment with sandy alluvial fans in vicinity of Mokelumne River
Geology/Soil Composition
San Joaquin series (shallow, sandy clay loam)
Climate
Mediterranean (among coolest in average degree-days in Lodi AVA)
Main Grape Varieties
Chardonnay, Viognier, Sauvignon
Blanc, Cabernet Sauvignon, Merlot, Petit Verdot, Primitivo/Zinfandel, Carignan, Petite Sirah, Barbera, Sangiovese, Tempranillo, Teroldego, Montepulciano, Nero d’Avola
Location/Geography
Southwest corner of Lodi AVA falling in San Joaquin County, skirting the Delta part of the Lodi AVA to the immediate west
Lodi’s largest AVA, comprising 34,681 ha/85,700 acres, and over 16,997 ha/42,000 acres of planted wine grapes
Name Background
Mokelumne River watershed area
Topography/Elevation/Water Sources/Geographic Features
3.5-26 m/10- to 85-feet elevation; fairly flat alluvial sandy loam deposits with no hardpan
Geology/Soil Composition
Tokay sandy loam series, up to 27.5 m/90-feet deep
Climate
Mediterranean (among coolest in average degree-days in Lodi AVA)
Main Grape Varieties
Zinfandel/Primitivo, Carignan, Cinsaut, Grenache, Alicante Bouschet, Cabernet Sauvignon, Cabernet Franc, Merlot, Malbec, Pinot Noir, Syrah, Grenache, Mourvèdre, Tannat, Barbera, Sangiovese, Aglianico, Montepulciano, Tempranillo, Graciano, Pinotage, Mission, Zweigelt, Blaufränkisch, Dornfelder, Chardonnay, Sauvignon Blanc, Albariño, Grenache blanc, Viognier, Roussanne, Piquepoul, Kerner, Fiano, Muscat Canelli, Flame Tokay
Location/Geography
93,077 ha/230,000 acres in Madera and northern Fresno Counties, within the San Joaquin Valley
Name Background
The AVA was named for the county and city of Madera. The county was also named for the city, which was given its name when the area became a distribution point for the California Lumber Company in 1876. Madera means “timber” in Spanish.
Topography/Elevation/Water Sources/Geographic Features
Low altitude and primarily flat, though a small portion extends into the Madera foothills.
Irrigation is required. The main water source is wells tapping underground aquifers. Due to high use and climate change, dry wells are becoming a serious problem for farms and residences.
Geology/Soil Composition
Most of the AVA has deep, alluvial soils. The Madera foothills feature Vista Sandy Loam of shallow, granitic schist
Climate
Steppe with heat summation indicating Winkler-Amerine Region V (hot)
Main Grape Varieties
French Colombard
Chardonnay
Cabernet Sauvignon
Merlot
Zinfandel
Location/Geography
121,41 ha/30,000 acres in the western foothills of the Diablo Range in Stanislaus County, seven miles southwest of Patterson and about 34 km/21 miles southwest of Modesto. It is to the west of Interstate 5 and southwest of the Salado Creek AVA.
This was established in June 1998 as a one-winery (Isom Ranch Winery & Vineyards) AVA with 14.2 ha/35 vine acres and plans for about 4 ha/10 acres more. The winery is no longer operating.
Name Background
The name was created by a resort development company, which created a community there in the 1990s. They named the resort and AVA after Mount Diablo and the Diablo range.
Topography/Elevation/Water Sources/Geographic Features
244-792 m/800-2,600-foot elevation, with slopes of 30% and greater. The vines range between 305-549 m/1,000-1,800 feet
Geology/Soil Composition
A jumble of sandstone based soils of varying depths: Arburua loam, Wisflat sandy loam, Contra Costa clay loam, and San Timoteo clay loam
Climate
Hot-summer, Mediterranean
Main Grape Varieties
Initially planted to Cabernet Sauvignon, Chardonnay, Merlot, Pinot Noir, Sangiovese and Syrah
Location/Geography
1,190 ha/2,940 acres at the foot of the Diablo Range in Stanislaus County, 29 km/18 miles southwest of Modesto. It is to the east of Interstate 5 and northeast of the Diablo Grande AVA.
The AVA was approved in June, 2004. There are no wineries in the AVA and no producer makes an AVA-designated wine right now.
Name Background
The AVA is named for Salado Creek, a seasonal stream that flows down from the Diablo Range and through the AVA
Topography/Elevation/Water Sources/Geographic Features
Flat to slightly sloping with altitudes ranging between 38.1-103.6 m/125-340 feet. The approximately 18 ha/45 vineyard acres are on flat land.
The AVA is crossed by the creek, but also a number of canals, ditches, and drains, most of which parallel the San Joaquin River, but connect to the river by a canal.
Geology/Soil Composition
The AVA sits on an alluvial fan formed by Salado Creek. The soil series is Ensalado
Climate
Hot-summer, Mediterranean
Location/Geography
A 526 ha/1,300 acre area in San Joaquin County, about 40 km/25 miles (40 km) due south from Stockton.
300 ha/740 acres are planted to vine.
Name Background
The name, used in the area since at least 1922, refers to the area’s location at the confluence of the San Joachin and Stanislaus Rivers.
Topography/Elevation/Water Sources/Geographic Features
The AVA is a shallow bowl. It’s bounded by the two rivers, along with river terraces, levees and floodplains.
It is crossed by numerous sloughs and small waterways.
Geology/Soil Composition
50% Merritt silty clay loam
25% Grangeville fine sandy loam
25% Columbia fine sandy loam
All the soils are highly fertile, very deep, and slow- draining, with high water-holding capacity.
Climate
Arid to semi-arid with some maritime influence. It’s the driest part of the Delta and cooler than towns to the north and east, such as Stockton and Modesto.
Diurnal shift is high. Daily highs are similar to Lodi.
Annual rainfall is about 25.4 cm/10 inches, almost all of which falls in winter.
Main Grape Varieties
Chardonnay and Cabernet Sauvignon
Location/Geography
A 15,864 ha/39,200-acre region, located in southwestern San Joaquin County and northwestern Stanislaus County. The AVA’s southeastern border is Interstate 5. Highway 205 is a short distance to the north. The town of Tracy is immediately to the northeast.
Name Background
The name “Tracy Hills” has been used for this zone for some time, as it lies near the foothills southwest of Tracy. The city, which was founded as a result of a new railroad line in 1878, was named after an Ohio railroad director, Lathrop Tracy.
Topography/Elevation/Water Sources/Geographic Features
The AVA includes two alluvial fans which slope down from the eastern face of the Diablo Range. The AVA runs from 152.4-30.5 m/500-100 feet in elevation.
Geology/Soil Composition
Alluvial soils washed down from the Diablo Range. Portions of the fans are very gravelly, promoting excellent drainage and reducing vigor.
Climate
Hot-climate Mediterranean
The area is subject to a somewhat more oceanic influence than AVAs further south, due to its proximity to the Altamont Pass.
However, it is shielded from direct winds by Mt. Oso, which also makes it drier and less foggy than nearby, non-viticultural areas which are closer to the Altamont Pass.
Main Grape Varieties
Cabernet Sauvignon, Merlot, Tempranillo, Sagrantino, Aglianico, Montepulciano, Nero d’Avola, Syrah, Touriga Nacional
Location/Geography
This 18,195 ha/44,960-acre AVA in the Sierra Nevada mountains of Fresno County, was established in 2015. It’s roughly 72 km/45 miles east of the city of Fresno. However, due to its altitude, this AVA may be considered just outside of and distinct from the San Joaquin Valley.
The AVA is in the Sierra Foothills, but far south of the Sierra Foothills AVA. Likewise, the Squaw Valley - Miramonte AVA is nearly 322 km/200 miles from the famous Squaw Valley ski resort.
Name Background
The AVA is named for two towns in its vicinity. One has been known as “Squaw Valley” or “Squawvalley” since 1879. The other has been known as “Rancho Miramonte” or just “Miramonte” since at least 1909.
Topography/Elevation/Water Sources/Geographic Features
Vineyards are on south- and southwest-facing slopes at altitudes of 488-1067 m/1,600 to 3,500 feet. Slopes in the area overall range from 5° to as much as 75°.
Geology/Soil Composition
Vista, Sierra, and Auberry series, all decomposed granite and well-draining.
Climate
Alpine, with more annual rain and a less dramatic diurnal shift, due to cooler days, than the valley floor to the west. Summers are nonetheless hot and dry.
Main Grape Varieties
A wide assortment of varieties grow in the AVA’s 2.8 ha/ 7 acres of vineyards, including: Chardonnay, Sauvignon Blanc, Vermentino, Viognier among the whites, and Aglianico, Barbera, Cabernet Sauvignon, Carmenere, Merlot, Petite Sirah, Syrah, and Zinfandel among the reds.
Location/Geography
This 23,472 ha/58,000 acre AVA in Kern County is at the summit of the southernmost pass in California’s Sierra Nevada mountains. It does not lie within any other AVA.
10 ha/25 acres are planted to wine grapes.
The AVA is at the extreme southern end of the San Joaquin Valley. Due to that, and the AVA’s altitude, it may be considered outside the valley.
Name Background
The AVA is named for the mountains in which it is situated. The mountains have been known by that name since at least the 19th century. It’s possible that local Native Americans used that name for the area long before then.
Topography/Elevation/Water Sources/Geographic Features
The AVA’s elevation ranges between 1,097-1,646 m/3,600-5,400 feet. Most vineyards lie in the lower half of that. Slopes are 3° to 11°.
Being a mountain pass, the topography is saddle-shaped, but with only moderately steep slopes.
Water sources for the AVA include springs and small streams fed by snowmelt.
Geology/Soil Composition
Triassic-period and later (before the mountains were formed) ocean sediment, with zones that are very rocky. The rocks are broken volcanics from the mountains which were formed much more recently.
Climate
The Tehachapi Mountains AVA climate is unique. It has both the cooling effect and high UV-exposure of a high- altitude growing site. But it also receives considerable warmth that rises from the San Joaquin Valley and Mojave Desert below. It’s possible to ripen grapes such as Zinfandel and Cabernet Sauvignon. Precipitation is scant, less than 203 mm/8 inches in an average year. That moisture comes almost exclusively during winter. It’s high Region II, borderline Region III on the Winkler-Amerine index.
Main Grape Varieties
Zinfandel, Viognier, Syrah, Tempranillo