36-48" x 18-24" (91-122cm x 46-61cm)
-30°F to -20°F / -34°C à -29°C (USDA Zone 4)
Very uniform habit has stronger stems than most and flowers faster. Low, mounding clumps of deep-lobed foliage and spikes of double deep blue flowers make an exceptional specimen in any border. Blooms in summer. Attracts butterflies and hummingbirds.