Reubens is a variety of Flattened Meadowgrass (Poa compressa). It is a perennial Meadowgrass, similar to Smooth-Stalked Meadowgras (Poa pratensis). It grows in old wall tops, cracks in the pavement, dry and rocky grassland and many types of other wild habitats. It has a flattened stem, which gives it its name. Flattened Meadowgrass grows to about 30cm tall. The preference is for full or partial sun and a slightly acidic soil containing sand, rocky material and/or clay.