Silvergrass Miscanthus 'Variegatus' - Hardy plantGrass metres tall! The silver grass 'Variegatus' (Miscanthus sinensis) can grow up to 1. 6 metres tall. The ornamental grass is winter hardy and doesn't need much maintenance. Ideal for a garden or border. We can plant this plant all year round. Provided temperatures don't go below freezing. The plant blooms with lovely plumes in the summer months. The plant does not require pruning. Just cut away the dead leaves. Put the plant somewhere in the sun.