Exploring Western Perennial Crop Cultivation in a Changing Climate

California wine grapes

Modeling Future Perennial Crop Suitability
Across the Pacific West, changing climatic conditions are encouraging farmers to reconsider their management practices, including the cultivars and crops they plant. This region, stretching from Oregon to Idaho and Washington to California, is home to incredible crop diversity. It produces many high-value perennial crops, including apples, blueberries, cherries, and wine grapes that rely heavily on irrigation from surface and groundwater sources during the dry season. Water is a precious commodity across the west and is at risk of declining due to climate change. Perennial plants live for decades and are thus at a disadvantage in terms of flexible adaptation, because of the time and costs required to re-plant and the years required in growth before a new field, orchard, or vineyard produces strong yields. In light of these challenges, guidance on how future climate conditions may influence site suitability, crop development, and water needs is useful for science-informed planning.

Climate change and weather variability is already affecting producers.
In California, warmer winters and springs have reduced chill accumulation for crops with high chill requirements. For instance, lower chill hours have led to early blooms for pistachio trees, whereas variable weather has led to frost damage in almond and citrus plants. Likewise, extreme heat and irrigation curtailments have led to damaged blueberries and apples in Washington. Climate change is projected to exacerbate these existing challenges, including: 

  • Increased temperatures across seasons, including more frequent extreme heat
  • Decreased snowpack and summer streamflow leading to potential water shortages
  • Increased extreme precipitation
  • Lengthened growing seasons
  • Increased plant moisture stress
  • Increased risk of pests and disease

* For more information on climate change adaptation for specialty fruit production in the Pacific Northwest, see Specialty fruit production in the Pacific Northwest: adaptation strategies for a changing climate and its references.

Future Crop Suitability Web Tool
The Future Crop Suitability Tool helps users understand potential crop success under future climate conditions, including what conditions might limit success. It models site suitability by taking into consideration temperature factors (allowing for or limiting cultivation), changes to the timing of crop development, and potential future irrigation demands for five high-value crops: almonds, apples, blueberries, cherries, and wine grapes (Chardonnay and Cabernet Sauvignon). Interested users can explore how changes in suitability, phenology, and irrigation needs change by crop, location, time, and future climate scenario, via the free webtool available through the Climate Toolbox and detailed here. The tool was developed by Katherine Hegewisch, Lauren Parker and John Abatzoglou, members of the Applied Climate Science Lab at the University of Idaho, Moscow.

  • Direct access to the tool and to user tutorials can be found on the Climate Toolbox website here. Details of the model parameters are available on the webtool's documentation tab.  
  • Addition information about the tool, including and sample queries and results can be view from this two-page tool summary, available on the Northwest Climate Hub website.


Contacts for more information:

Holly Prendeville, USDA Northwest Climate Hub Coordinator, holly.prendeville@usda.gov

Lauren Parker, USDA California Climate Hub Postdoctoral Fellow, leparker@ucdavis.edu