As the name might imply, this is
a sport of H. 'Sum and Substance' which was introduced by
Jan Van den Top but has not been registered. It also becomes a huge
mound of foliage. The leaves are moderately corrugated,
have deeply lobed margins, are cupped both up and down and have a
long, distinct tip. It has thick substance which makes it
resistant to slug damage. In late July and into August, it
produces large pale lavender flowers on four foot tall scapes.
Similar cultivars include H. 'Lady Isobel Barnett' and H. 'Sum It Up'.