Introduction to Hollies
When you think “holly,” you would be forgiven for automatically thinking “evergreen and spiny,” since many of them are. But did you know that there are exceptions, and that a few of the exceptions are also native? Multiple types of holly can be grown in our area, and all have their uses with regards to screening, hedging, wildlife value, decoration and security. Below is a guide to all of the commonly-encountered forms. All of these hollies are either male-flowered or female-flowered, and in almost all cases, in order to get berries on the female plants, a male of the appropriate type is needed for pollination. Several female plants can be pollinated by one male if the distance between them isn’t too great (the bees will find them anywhere in the average yard). Most hollies with leaf spines will also lose some spinyness over time – leaves on mature growth will be smoother and leaves on younger growth will be pricklier. Birds do enjoy holly berries, but often leave them for last as they prefer other fruits instead. This means more decoration for you before the hungry birds gorge on them in mid- or late winter. The good news is, most hollies are perfectly at home in full sun or mostly shade, and aren’t picky as to soil type so long as it’s not soggy (for most) nor very dry.
This species is best for drought tolerance and is moderately to exceptionally prickly, depending on variety. Berries are red and can appear on plants that weren’t pollinated, which is a benefit for those with limited space to devote to a male holly. Like many hollies, they prune well and make great hedges and security barriers (those really spiny varieties are great at deterring deer, unruly children and unwanted snoopers). The “Dwarf Burford” variety is one of the most commonly used and one of the least-spiny options. ‘Rotunda’ is the form you want for that “don’t even think about it” level of sharpness.
Looking very much like boxwood, their leaves are small and spineless, and any berries that may be produced are black. Although there are some golden forms, leaves typically are dark green and glossy. Growth habits are dense and plants are easy to trim and maintain as a hedge or foundation border.
Named for their inky-black berries, these are native to all of the eastern and gulf states and occur in colonies in swamps and moist soils. In gardens they rarely sucker and don’t need wet conditions so long as they don’t dry out too much. Naturally more open with sparser interiors, their foliage that is still dense enough to block a view if they aren’t pruned too rigorously. Our most cold-hardy of the evergreen hollies, they can occasionally take on a purplish blush in winter, but are otherwise a rich, bright, glossy green. Birds appreciate the berries and shelter they offer, and they make good additions to rain gardens and other naturalistic gardens. Deer dislike the foliage for some reason (presumably taste), so this makes it the only spineless holly that should be reliable for areas visited by deer.
“Blue” Hollies (a.k.a. “Meserve” Hollies)
This is the name for a group of hybrids initially developed by a woman on Long Island in the 1950s. They have good cold-hardiness and, despite their mixed parentage, tend to have dark green leaves, purple-black stems, and red berries. (We’re not sure where the “blue” comes from…perhaps because they’re not the brighter, truer green of most other hollies.) Leaf spines tend to be gentler, and plants are easily trimmed to meet the needs of a screening hedge or shorter foundation row. There’s even a lovely marbled variety named ‘Honey Maid’ that has light yellow leaf accents.
Very much like Japanese Hollies in appearance, their leaves are small and spineless, except that these produce red berries. Native to the southeast, we are at the upper end of their cold tolerances, but only a harsh winter and an exposed planting site would give them winter damage. Although not naturally found in Maryland, they make great winter-interest additions to wildlife and Bay-friendly gardens. If you have had trouble with Japanese Hollies due to overwatering, try Yaupon, as they are a bit more resilient in this regard.
Not commonly used in Maryland, this is also near the upper end of its cold tolerances here, though the variegated forms seem to do best. Berries are red on the female variety, which gets the size of a small tree, and the leaves are edged in creamy yellow. The male, ‘Gulf Coast,’ is a dwarf, shrubby form with deeper yellow leaf edges. Because of their leaf sharpness, this is one of the only hollies we’d consider reasonably deer-resistant.
Our other native evergreen holly, which grows to the size of a small tree, is great for woodland plantings (where you’ll see it in the wild) and wildlife gardens alike. Tolerant of wetter soils and not prone to deer browsing, it’s a great long-lived choice if you can manage its slow growth rate. Hard to find in nurseries because of this (getting them to a sellable size while still looking straight and dense takes some doing), they’re common in landscapes as older specimens but scarcer otherwise. Berries are red and mature leaves tend not to be glossy like they are in other hollies.
This is a double surprise – no spines on the leaves and no leaves in winter! (Which is a good thing, since the berries are very showy and best seen when the leaves are gone.) The most prolifically-fruiting holly, the stems are covered in a foot or two of bright red, orange, or golden berries most of the winter. Heights vary, but their bare-bottomed habits provide the opportunity for great companion plantings. Soil should be moist but can even be quite wet, and while full sun gets you the best berry count, they’ll tolerate lots of shade and can be found growing in open woods in the wild.
Miscellaneous Hybrid Hollies
This is a catch-all group, because their parents hail from all over the evergreen holly spectrum, but in general, they’re dense pyramidal large shrubs to small trees. Berries are red and leaves have moderate spinyness. Popular varieties include ‘Nelly Stevens’ and ‘Oakleaf’.