Clematis heracleifolia 'Cassandra', Non-vining Clematis

Large, 6-inch leaves surround a smaller flower, but the flowers come in droves and are made for the lover of blue: trumpets of violet-blue to azure blue (depending upon bloom stage), with dramatically recurved petals, a slight ruffle at the edges. This is a shrubby form, 2 – 3 feet tall, with clustered, honey-scented flowers blooming mid-summer to early autumn.  Minimum temperature: -20° F