From late fall through winter Ilex verticillata produces a grand
display of bright red berries that persist and light up its
branches long after all of the leaves have fallen. Commonly
called winterberry, but also known as Michigan holly or swamp
holly, this is a deciduous type of holly for cold climates. They
perform best in full sun and acid moist soils. Therefore, they
need to be watered and given acid fertilizer in July and August
if there has not been good rainfall. Winterberries flourish best
in zones 3 through 9. Only the female winterberry plants produce
the colorful berries, therefore, gardeners should plant one male
near 3 to 5 females to ensure good pollination and fruiting. In
a large planting it is best to include both early and late
blooming male shrubs to maximize pollination of the females.
Some different variations of winterberry for pollination
purposes are: - ‘Jim Dandy’: a slow growing dwarf male useful
for pollinating early flowering females such as: - ‘Red Sprite’:
a popular dwarf female