1. Top of the Valley
Calistoga is at least 300 feet above sea level, with vineyards up to 1200 feet above sea level.
VINEYARD PERK: Higher elevation means cooler temperatures at night, for better growing conditions and ultimately better structure in wines.
2. Most Diurnal Change
Calistoga AVA has the most extreme diurnal swing in Napa Valley of all AVAs, meaning the day time and night time change in temps is very large.
VINEYARD PERK: Having a large diurnal shift means the grapes can relax and respire at night after a warm day, allowing for more acid retention; better overnight recovery, thus better balanced wines.
3. Highest Percentage of Volcanics
Of all the soil series in Napa Valley, Calistoga AVA has the highest percentage of volcanic type soils.
VINEYARD PERK: Volcanic soils yield more minerals for limiting nutrients that grapes need and allow for better drainage which is better for root development. Further, thinner volcanic soils lead to less green growth and more concentration of flavor within the berries.
4. Russian River Basin Coastal Air Movement
Cooling breezes come through the Northwest corridor above and to the west of the Calistoga AVA for cooling during warmer periods. Air movement in afternoons is a result of Mount St. Helena and Palisades “air pump.”
VINEYARD PERK: Breezes cool things down during normally stagnant air-flow periods in other AVAs. Ideal growing conditions with cooling breezes allow for acid retention, better humidity control, mildew control and better structure and ageability in grapes.
5. Excellent Aspects
Calistoga AVA has the highest ratio of steep slopes to valley floor of any AVA.
VINEYARD PERK: Sloping vineyards/hillside typically have weaker, but better drained soils contributing to grapes with higher concentration and power.
6. Consistent Geology
The entirety of the Calistoga AVA is underlain by volcanic bedrock and sediments more geologically uniform than other Napa Valley AVAs with valley floor environments.
VINEYARD PERK: Uniform soils throughout the region enable growers to control vine quality and produce consistent flavors and characters within small vineyard block areas much better.
7. Best Rainfall
The highest recorded rainfall every year is in the Calistoga AVA, especially on the higher elevations.
VINEYARD PERK: Grapes do not suffer from water shortages in average years and many growers can actually dry farm their grapes and still achieve optimum quality due to heavy rainfall and storage in the winter.
8. Slope and Sun
Calistoga AVA slopes and geological fans have unique sun exposures.
VINEYARD PERK: The slope to sun exposure angles provide opportunities for optimum vine growth in areas where insufficient light would normally cause viticultural quality issues. Optimum light during the growing day is critical for the physiological activity of the grapevine.
9. Single Climate Region
There is little variation in climate within the Calistoga AVA region.
VINEYARD PERK: Having uniform meso-climate from area to area and from vintage to vintage allows growers to farm efficiently and control grape quality much easier compared to other AVAs throughout Napa Valley.