Evaluating farmers' adaptation strategies amid rising heat and climatic extremes in San Diego County, California

California's agricultural sector faces intensifying climate risks, yet research has concentrated on large commodity production regions, leaving small-farm and specialty crop systems underexamined. San Diego County, home to more than 4000 farms dominated by small-scale operations, high-value perennial tree crops, and the state's largest concentration of certified organic producers, faces compounding drought, extreme heat, wildfire, and high water costs. This study employed an exploratory sequential mixed-methods design integrating projections from the Community Earth System Model version 2 large ensemble, 10 semi-structured farmer interviews, and a survey of 119 farmers. Projections indicate sustained warming and an increasing frequency of days exceeding 104 degrees F (40 degrees C) through 2050. Drought and high temperature were the dominant concerns, with 84% and 77% of respondents reporting moderate or high concern respectively. Presented with the projections directly, avocado growers reported the highest crop-level heat concern (67%), consistent with a 31% decline in county avocado acreage between 2017 and 2022. Irrigation modernization was the most widely reported adaptation strategy (79%), followed by soil management (49%) and crop diversification (36%); 11% reported no adaptive action. Farmers applied the same core strategies across all five hazards rather than matching strategies to hazards: of 25 hazard-strategy pairings tested, only three showed elevated adoption after correction for multiple comparisons, indicating that perceived feasibility rather than hazard diagnosis governs adaptation choice. Embedding localized projections directly in a survey instrument is rarely done in farmer perception research. Findings highlight the need for extension programs and policies tailored to farm scale, crop type, and water access in small-farm specialty crop systems facing escalating climate exposure.