The result of crosses
aquifolium and I. latifolia are
called I. × koehneana hollies.
These plants have turned out
to be as hardy or more hardy
than either parent. They have
survived winters to -7°F
with very little damage. The
star of the family is 'Lassie'.
It was discovered by Stuart
McLean and registered
by the Holly Society in 1970, registration
'Lassie' grows quickly, averaging 8–10 inches (20.3–25.4 cm) each year until it reaches a height of 20–25 feet (6.1–7.6 m) at maturity. Situated in full sun, it will retain a pyramidal shape with little pruning.
The leaves are long and glossy green with many short spines. The plant has been compared to the evergreen southern magnolia (Magnolia grandiflora).
'Lassie' is a female holly that never fails to set fruit if a pollinator is nearby. It seems to be the earliest in its family to set fruit, even fruiting the first year. The berries are shiny, vivid red and 5/16 inches (7.9 mm) in diameter. Male pollinators include I. × koehneana cultivars 'Ajax', 'Chieftain', 'Jade', and 'Loch Raven', although English and other hybrid male hollies that bloom at the same time will do.
'Lassie' has earned the Gene Eisenbeiss Holly of the Year Award for 2005. Koehneana hollies and especially 'Lassie' will soon be favorite landscape plants.
Ilex × koenheana 'Lassie'
Photo by Bill Cannon