Flower Carpet groundcover roses from Anthony Tesselaar Plants are a simple solution for landscaping a slope. The Flower Carpet series has won the most awards for disease-resistance, most notably Germany’s coveted All Deutschland Rose (ADR) designation, the world’s top honor for disease-resistant roses. These plants root deeply and therefore keep the ground from washing out – so they’re good for the soil/location itself. Once established, they’re pretty drought tolerant – good for slopes, which often tend to dry out and become impervious to water.