Kenneth D. Cochran, Secrest Arboretum of The Ohio State University Ohio Agricultural Research and Development Center, Wooster, Ohio; and James A. Chatfield, Ohio State University Extension, Northeast District and Department of Horticulture and Crop Science.
Ilex verticillata (Michigan winterberry)
Ilex verticillata 'Winter Red,' 'Winter Gold,' and 'Red Sprite' are deciduous holly selections of superior phenotypic expression for ornamental purposes and habitat preference. The name tells the fruit color, and they are abundantly produced along the stem, persisting through the winter in mild years. 'Winter Red' and 'Winter Gold' are multistemmed medium-sized shrubs, and 'Red Sprite' matures to a small- to medium-sized compact shrub.
Where evergreen hollies cannot be grown in colder parts of the country, winterberry holly plants appear to be of greater use as northern selections. They are relatively unaffected by sub-zero winter temperatures, but red berries will blacken under extreme cold. Lack of moisture during flowering affects pollination as with most hollies, and drought conditions during the heat of summer will bring wilt to established plants, and, if supplemental water is not applied, fruit will be smaller and fruit retention will be reduced. Plant in full sun.
The species is native to bog and swamp areas, and it is tolerant of lowland areas in the landscape, but it grows well in good garden soil. Avoid plants in high/dry sites. Due to differences in blooming time among the various selections, female cultivars should be matched with certain male cultivars in order to assure abundant fruit set.