Agricultural diversification toward plantation crops has significantly transformed farming systems in several regions of India. This study analyzes cropping pattern changes and the expansion of plantation crops in Dakshina Kannada and Kodagu districts of Karnataka. Secondary data and trend analysis, regression models, benefit–cost ratio analysis, and sustainability indicators were used to evaluate agricultural transformation. Results indicate a significant decline in rice cultivation and expansion of plantation crops such as coffee, coconut, arecanut, rubber, and cashew. Plantation crops demonstrate higher economic returns and improved land productivity. However, sustainability challenges such as soil degradation and climate variability require balanced agricultural planning.