MontRubí works with Sumoll, a native Catalan variety rooted in Penedès. The winery's focus centers on this grape across several expressions: Gaintus Radical Sumoll, Gaintus Vertical Sumoll, and Gaintus Sobremadurado each explore different dimensions of what the variety can express. Wine Advocate and Wine Enthusiast have rated these wines. Sumoll itself is a dark-skinned grape with mineral character and structure, capable of aging. In Penedès—a region spanning the coastal plains and inland hills of Catalunya—producers work with Mediterranean conditions and diverse soils to craft wines across multiple styles. MontRubí's commitment to a single variety, across multiple bottlings, suggests a deep investigation into terroir and winemaking technique rather than breadth across the portfolio.