The Hollies

Family: Aquifoliaceae (Holly family)
Genus: Ilex
Species: more than 400!!

If you have so many relatives that you wonder how you’re going to fit them all around your holiday table this season, consider that it could be worse…you might be a Holly, a member of the Ilex genus. If you invited all of them over for dinner, it would require a large table, indeed. And they come from all over the world! Some would travel from their native Scotland, others from the Canary Islands or Turkey, the Himalayas or Florida, Japan, California, or Korea. It might be hard to recognize them as relatives, since they come in so many shapes and sizes and colors. Some would stand tall and be quite prickly; others would have fewer rough edges but tend to sprawl. A few would prefer to stay out of the cold, but most could handle at least a short outing in the worst of Whatcom winters. None of them would eat you out of house and home. A few would tend to tipple a bit, but most wouldn’t mind staying dry. Almost all would add to the holiday festivities with their red, orange, yellow, or black berries.

There is a holly for every taste. The best known is probably Ilex aquifolium, the classic English holly that is associated with Christmas greenery. The species is well suited to our Pacific Northwest climate. An evergreen tree of pyramidal form, I. aquifolium can exceed 30 feet in height. There are many cultivars and clones, offering variegated leaf color—creamy or golden edges, even green polka dots!—as well as choices in eventual size, rate of growth, leaf form, and stem color. There is even at least one weeping variety, I. aquifolium ‘Argentea Marginata Pendula’. Other species offer many more choices, from I. crenata—Japanese holly, generally small shrubs with small to tiny leaves—to I. verticillata, the deciduous winterberry. Many hollies provide interest in late spring with small flowers—those of Ilex aquifolium are white and fragrant.

A large number of hollies, both deciduous and evergreen, are hardy here, although check carefully when you choose your favorite. Some choice specimens are markedly less hardy than others. It’s also important to check the sex of your chosen holly and its pollination requirements, if you’re counting on a display of berries. Most hollies are unisexual; the female plants produce the berries but require a male holly of the same species in the vicinity to do so. The general neighborhood will do, thanks to bees; but simultaneous flowering is crucial. They need not be planted one-for-one—a single male plant will pollinate a dozen or so females. Hybrids can be pollinated by either parent. There are also hollies that are self-pollinating, and a few that have been developed for the sole purpose of pollinating a particular female variety. There are also sterile male clones—plants so attractive that they’re judged to be worthwhile, even berry-less. These details, along with precise cultivation requirements, should be clearly marked when named specimens are sold. As a rule, hollies prefer rich, well-drained soil, full sun, and ordinary watering and feeding. Many will not tolerate alkaline soil and don’t do well when planted close to concrete foundations, driveways, or sidewalks. They have shallow root systems, so use care when cultivating around their bases and consider mulching as a barrier to weeds.

Hollies in our area seem not to be bothered by diseases, but they are susceptible to certain pests, including holly leaf miner and several kinds of scale. A comprehensive list is found in EB0826 in your Master Gardener materials, along with treatment options. But don’t let the possibilities of infestation interfere with your enjoyment of this beautiful family during the holiday season—no treatment is indicated (or will be effective) until 2000 anyway! So invite some members of the holly family to your celebrations as decorative guests—go ahead, deck the halls! Best wishes for the happiest of holidays and the merriest of new millennia…from my heart to yours.