Rattlesnake Hills AVA Overview

Rattlesnake Hills AVA

The Rattlesnake Hills AVA is the ninth federally recognized American Viticultural Area and is entirely contained within the the Yakima Valley AVA. The hills form the northern boundary of Yakima Valley, and the AVA includes land between the northern bank of the Sunnyside Canal and the entirety of the southern slopes of the Rattlesnake Hills between Outlook and the Wapato Dam. This AVA is centered on the city of Zillah and contains the highest point within the Yakima Valley AVA.

Rattlesnake Hills AVA is comprised of approximately 68,500 total acres. The primary grape varieties in the region include Riesling, Merlot, Cabernet Sauvignon, and Chardonnay. Due to the wide range of elevations throughout the AVA, there is less risk of a spring or fall frost endangering the vines. Average rainfall throughout the AVA ranges from 6 to 12 inches annually. In addition, fine, shallow, silt loam soils in this AVA that are left over from the ice age are the ideal soil for producing grapes.

Climate and Soils

With rich Warden Silt Loam soils, Rattlesnake Hills AVA receives 7-8 inches of rainfall annually and 2680-2870 annual degree days – an optimal combination for producing world calss wine grapes.

The Rattlesnake Hills AVA lies within both the established Columbia Valley and Yakima Valley appellations. There are several components that distinguish the 68,500 acres of the Rattlesnake Hills area from the surrounding areas. These components include a unique mix of temperature, soils, and climate.

The tall Cascade Range to the west shields the Rattlesnake Hills and much of eastern Washington from the impacts of the ocean. The Umptanum Ridge, Yakima Ridge and the Rattlesnake Hills ridge line covers the vines from the freezing polar air carried down from Canada. This freezing air can severely damage or even kill the vines, so this protection is essential to the growth of the vines.

As a result of this rich combination of elevation, soils, precipitation and heat units creates an ideal growing region for those with a vineyard vision.

ELEVATION: 860 to 890 Feet
SOIL: 100% Warden Silt Loam
SLOPE: 2%-15% across the property
RAINFALL: 7-8 inches per year
HEAT UNITS: 2683-2870 annual degree-days
WIND: Predominantly from the Southwest

Water and Precipitation

Yakima County Precipitation Map for Rattlesnake Hills AVA
Pond on Property Close-Up
  • Annual rainfall for this area averages 7 to 8 inches per year.
  • Sunnyside Valley Irrigation District to provide 3-acre feet per acre of water rights, annually assessed for unlimited water usage.
  • The irrigation water is currently fed into a lined pond on the property where it is pumped through the sand filtration system and delivered to the vines via drip irrigation system.
  • Water service is accessed from a domestic well that serves both the main production facility and the main residence.
  • The tasting room, original production area, and the guest residence are served by a second well.
  • There are separate septic systems from each residence and two separate systems for the production facilities.
  • Waste water for the production facilities and residences has typically been run into the on-site septic systems.


The approximately 9.5-acre vineyard produces over 40+ tons of wine grapes per year from 6,000 vines and 11 varietals. These varietals include: Cabernet Sauvignon, Syrah, Sangiovese, Nebbiolo, Viognier, Chennin Blanc, Marsanne, Sauvignon Blanc, Pinot Gris, Malbec & Grenache. The entire 2021 wine grape output is under contract with several nationally and internationally recognized Pacific Northwest winemakers.

The Yakima Valley AVA grows more than 40 different varietals of wine grapes. The success of this diversity can be attributed to the many different growing aspects within the AVA. The micro climates, heat variations, and different soil types within the AVA are factors in the ability to successfully produce different varieties.

Some wineries that use the grapes produced in the Rattlesnake Hills AVA include Chateau Ste Michelle, Hyatt, Saviah, AniChe Cellars, and Kennedy Shah, just to name a few.

Currently Planted Varieties

Sauvignon Blanc0.37 +/- acres
Marsanne0.65 +/- acres
Nebbiolo0.99 +/- acres
Cabernet Sauvignon2.36 +/- acres
Sangiovese1.38 +/- acres
Chenin Blanc0.76 +/- acres
Viognier0.90 +/- acres
Syrah1.93 +/- acres
Pinot Gris0.32 +/- acres
Malbec0.05 +/- acres
Grenache0.02 +/- acres