'Hummelo' Alpine Betony was named after Piet Oudolf's hometown. The low growing rosette of textured green leaves is topped by showy spikes of lavender-pink flowers in mid summer for an extended period. Stachys 'Hummelo' is a tough, carefree beauty and used extensively on the High Line Park in NYC. If you haven't gone there yet, go soon! 2019 Perennial Plant of the Year.