When we think of hollies (Ilex), we often picture shiny, green, prickly leaves and red berries decorating winter holiday scenes. Yet these plants deserve much more than one month of adoration. Continued crosses between North American, European and Asian species have produced an ever-expanding, ever-improving range of cultivars to fulfill many needs in the garden, all year long.
Most hollies thrive in those tricky, sheltered part-sun spaces where shade-loving evergreens might burn or become stressed, and where sun-loving evergreens, such as boxwood, might grow leggy or fall to disease. Many Ilex species tolerate moist conditions and maritime, coastal climates, and they prefer acid soil. In spring, their blooms provide an important early source of nectar for bees and other pollinators—an often-overlooked attribute because the blossoms are not showy. Their berries (technically drupes) are a favorite for birds and wildlife. Hollies are usually dioecious, meaning that distinct male flowers and female flowers occur on separate plants. (In contrast, monoecious species have male flowers and female flowers occurring on the same plant. There are also plants whose individual flowers possess both male and female parts—these are known as perfect flowers.) Female hollies will bear fruit only if a male plant grows in the vicinity—important to know when planning the garden and shopping for plants.
Excluding the straight species of English holly (Ilex aquifolium), which has become an invasive pest across mild climates in North America, here are a few safe varieties that show the scope of the genera’s versatility:
Space-Saving Evergreens
For smaller hedging and dwarf foundation shrubs, Ilex crenata (Zones 6–9), or Japanese holly, is king. Often compared to boxwood, they are such master chameleons that many can fool most casual garden visitors. Utilitarian but tough, Japanese holly is best known for its columnar varieties ‘Steeds’ and ‘Sky Pencil’, but the shrubbier varieties—such as the two- to three-foot ‘Soft Touch’ and 'Hoogendorn'—that get the most mileage in the garden. ‘Helleri' forms a beautiful four-foot-tall and five-foot-wide rounded shrub that require little to no pruning. This holly is grown just for its foliage, not its berries, and there are yellow-leaved cultivars on the market, including Brass Buckle ('Annys1') and 'Golden Gem'.
Ilex glabra, or inkberry, is the eastern North American native cousin to I. crenata, offering shade-tolerant, soft-textured, boxwood-like shrubs that grow from three to five feet tall and wide. Many gardeners grow inkberry holly solely for its foliage, but the female varieties delight winter birds with their purple-black drupes.
While the species is often rather spreading and airy, commonly found female varieties ‘Compacta’ and ‘Shamrock’ (Zones 4–9) and ‘Densa’ (Zones 5–9) are all known for their leafier and more compact habits. They can grow about four feet tall and three feet wide. ‘Shamrock’ has exceptionally bright green new growth. The form leucocarpa and its selection ‘Ivory Queen’ bear unique white to soft yellow berries. The male pollinator for all of these female inkberries is Nordic (‘Chamzin’; Zones 3–9), which stands four to five feet tall. For a very small inkberry, seek the newer cultivar Strongbox ('Ilexfarrowtracey'), introduced as a two-foot, densely leaved, low-maintenance alternative to boxwood.
Red-Berried Options
Ilex vomitoria, or yaupon holly, is another US-native, small-leaved holly; it’s a great substitute for I. crenata and I. glabra in the South and at the coast. Yaupon can withstand a broad range of conditions, including wet sites. The male 'Stokes Dwarf' (syn. ‘Schillings’; Zones 7–11) is an excellent spreading shrub, slowly growing two to three feet tall and three to four feet wide. 'Pendula' (Zones 7–9), a unique female weeping form reaching 10 to 15 feet tall and 8 to 10 feet wide, ripens bright red berries in fall.
A perfect companion for any yaupon holly would be the Koehne holly, I. x koehneana (Zones 6b–9), long lauded by garden writer Adrian Higgins. Its large, almost chestnut-like dark green leaves make it stand out. A pyramidal specimen for driveways, paths and fields, it grows a distinct 20 to 30 feet high and half as wide. Males include ‘Ajax’ and ‘Chieftain’; female varieties are ‘Wirt L. Winn’ and ‘Agena’. The variety ‘Jade’ is a squat four- to six-foot shrub. Properly paired, Koehne holly is a large producer of berries.
For classic pyramidal form and dramatic leaf shapes, the so-called red hollies are hard to beat. The red hollies are a series of hybrid plants first introduced in the 1990s as downsized alternatives to mainstays like ‘Nellie R. Stevens’ and the large American holly (I. opaca).
All red holly hybrids are winter hardy in Zones 6 through 9. Robin (‘Conin’) is the largest red-holly offering, comparable to ‘Nellie Stevens’ and able to make a large hedge or specimen featuring maroon-colored new foliage and heavy berry production in fall. It quickly grows to 12 to 20 feet tall and 8 to 12 feet wide. Oakleaf (‘Conaf’) features a very bold pyramidal shape to 14 feet tall and 8 feet wide, with unique, flat, lobed leaves. It’s a self-fruiting, perfect-flowered variety (no need for a partner!) that bears small, orange-red berries and makes a knockout screen or hedge. Look, too, for Oakland (‘Magland’), a further improved version. The variety Liberty (‘Conty’) offers dense coverage with its dark green, deeply serrated leaves, but it remains a modest six- to eight-foot-tall, four- to six-foot-wide conical tree. With its winter interest of berries, it’s perfect for group plantings or tucked wherever that classic holly look is required.
Gorgeous Deciduous Hollies
Deciduous hollies drop their leaves in fall, making way for stellar winter interest both in the garden and cut arrangements. Free of prickles, these species are also often hardier than their evergreen counterparts. The North American Ilex decidua is an upright, rounded shrub or spreading small tree hardy in Zones 5 through 9. Also known as possumhaw, it grows 6 to 15 feet tall and wide. The cultivar 'Warren's Red' will fruit heavily if planted near a male pollinator such as ‘Red Escort’. ‘Byers Golden’ is another notable female variety, one with yellow berries.
The winterberry hybrids (I. verticillata), also native to the US, are even hardier. Red Sprite (‘Nana’; Zones 4–8) is a border-friendly dwarf at three to five feet, as is the similarly sized Berry Poppins (‘FarrowBPop’; Zones 3–9). Male cultivars ‘Jim Dandy’ and Mr. Poppins (‘FarrowMrP’) serve as great pollinating partners for these. Little Goblin is an even smaller fruiting winterberry; it's available in red- and orange-fruited versions, with Little Goblin Guy their pollinator.
The genus Ilex offers a truly remarkable diversity, with new cultivars appearing in quick succession. Explore Ilex as a gift box of endless interest; you’re sure to find a holly perfect for your garden.
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Image credits:
Brass Buckle, Strongbox and Berry Poppins: Proven Winners
Yaupon holly: Alabama Extension/Public Domain
Koehne holly: Leonora Enking/CC BY SA-2.0
Oakleaf red holly: John Paul Endicott/CC BY 2.0
Possumhaw holly: sonnia hill/CC BY 2.0
