IMPLEMENT: VITICULTURE ADAPTATION

Managing for Climate-Adapted Vines

Across all winegrowing regions of the world, climate change impacts are already apparent and demonstrate a multitude of challenges, most notably seasonal variability and chaotic weather fluctuations. Adapting vineyard development and viticultural practices to withstand stressors like heatwaves, droughts, floods and altered growing seasons ensures sustainability against ever-changing and unpredictable environmental conditions. To build resiliency to current and projected impacts, winegrape growers must make viticulture management decisions based on their vineyard’s vulnerabilities and risks in the face of climate change. The information below will help growers create flexible strategies and identify adaptation practices suitable for current and future challenges.

Priority Practices Quick Links:

Building Resiliency to Climate Change Impacts with Climate Smart Vineyard Design

When planting or replanting a vineyard or block, there are key elements to vineyard design that can have lasting benefits in a changing climate. Most importantly, strategically choosing both rootstock and scion can improve the resilience of vineyards to climate change. Vineyard design considerations such as row orientation and trellising, along with canopy management practices can further increase the resilience of grapevines. By understanding the climate risks that are most likely for your vineyard site, you can tailor your selections and design considerations to address water stress, increased erosion potential, and/or high heat events.

Selecting Rootstocks & Scions for Climate Resiliency

When selecting rootstocks and scions to plant in a new or replanted vineyard, consider what climate change impacts are predicted for your region. Choosing rootstocks and scions that are well-suited for current and predicted changes from climate change will ensure your vineyard’s sustainability. Rootstock selection can affect vine growth, yield and disease resistance with limited influence on berry quality. Generally, high vigor rootstocks can better access water in dry years and have longer growing seasons, while low vigor rootstocks may better resist extreme drought because of their smaller canopies. Also consider rootstocks that resist soil-borne pests present in the region or pests that may be exacerbated by climate change.

Various scions provide different adaptive benefits and can be more resilient to climate impacts such as increased drought, changing seasonality, extreme heat, frost, and pest and disease pressure. When choosing a scion consider:

Phenology: Late-ripening varieties such as Grenache, Monastrelle and Petit Verdot can mitigate the effects of compressed development.
Heat Tolerance: Cabernet Sauvignon, Zinfandel, Grenache and Syrah are known to be better suited for warm climates.
Drought Tolerance: Look for varieties with high water use efficiency to handle increased water stress. Cultivars associated with warm and dry climates, like Cabernet Sauvignon, may also be better suited for drought conditions.

Rootstocks & Scions

Changing Seasonality: Varietal-Specific Vulnerabilities

Recent research describes how modeling for six winegrape varieties in 12 of California’s AVAs show potential changes in phenology and environmental conditions:

Compressing of Development: Results show more rapid development for winegrapes with earlier budburst, flowering, veraison, and maturation across all varieties and AVAs. Cabernet Sauvignon shows the greatest change in phenology timing, while Chardonnay shows the least change. Projections of Pinot Noir development show chill being delayed by 1-3 weeks and maturity occurring 1-3 weeks earlier.
More Extreme Heat: Heatwave events (extreme temperatures lasting for consecutive days) decrease berry size and influence berry chemistry which can impact yield and quality in many cultivars. Heatwaves can be hazardous to worker safety and productivity.
Increased Water Demand: Warmer temperatures and more extreme heat days will increase water demand, which in some regions may be exacerbated by decreased winter precipitation which is necessary for soil moisture recharge.
Less Changes in Warmer Climates: Warm-climate AVAs like Lodi and Madera will see less drastic changes in winegrape phenology than cooler-climate AVAs like West Sonoma Coast and SLO Coast.

To learn more about the research findings including more specific information by AVA, watch this video summary or see the research paper, “A variety specific analysis of climate change effects on California Winegrapes” (Parker, et al., 2024).

Vineyard Design & Canopy Management Can Help Regulate Extreme Temperature and Sun Exposure

Vineyard design and canopy management practices can offer significant protection to grapevines against climate change. Vineyards designed with east-to-west trellising are more resistant to temperature extremes than those running north-south, although other factors such as site topography can influence the preferred orientation. Grapevines with elongated trunks are more resistant to temperature extremes than those close to the ground. Orienting vineyard rows to minimize erosion is also important, particularly when heavy rain events follow periods of dry weather that have diminished the soil’s capacity for water absorption. Using canopy management techniques like leaf thinning and shoot trimming can help regulate canopy temperature and sun exposure. Vineyard pruning and thinning practices may increase soil carbon storage if the extracted biomass remains in the vineyard. Similarly, the dropping of fruit can be a valuable carbon input. When developing a new vineyard site conserving existing native perennial vegetation can preserve sources of carbon storage. Planting hedgerows with native vegetation when existing plants cannot be maintained enhances the surrounding habitat by providing areas for beneficial insects to flourish to help with pest pressures.

Vineyard Design & Canopy Mgmt

Preparing for Wildfires

Climate change is already creating changes in wildfire dynamics, leading to increases in extreme wildfire events, which can indirectly impact grape and wine quality through vineyard smoke exposure. Climate science shows these extreme wildfire events are likely to continue to increase in the future. It is important to ensure your property and staff are prepared for a potential fire. Visit the resources below to help you prepare.

Wildfire Preparedness Resources:

A Winegrower's Guide to Preparing for Wildfires: Includes a checklist with steps to take to reduce the risk of fire on your property and how to prepare your vineyard or winery staff in the event of a fire.
West Coast Smoke Exposure Task Force: Includes relevant research and industry resources on best practices, crop insurance, wildfire preparedness, informational videos, etc.
Wildfire Preparedness & Recovery Resources: Wine Institute has compiled resources to help winegrowers proactively prepare for the risk and threat from fire season.

Wildfire Preparedness

Viticulture Adaptation Resources:

Viticulture Adaptation Implementation Guide: This guide provides details and resources about adaptation practices related to vineyard design and rootstock and scion selection.

Managing California’s Vineyards for Resilience: Strategies for a Changing Climate: A summary handout of the findings of a recent literature review conducted by the USDA California Climate Hub that synthesizes the key climate change impacts that will affect California vineyards.

Climate Change and California's Winegrapes: An educational webpage/StoryMap created by the USDA California Climate Hub that covers the projected impacts of climate change on winegrape phenology, the adaptation and mitigation strategies currently available to producers, and the gaps in research and technology that must be addressed to protect the future of winegrape production in the state.