Ilex crenata 'Icoprins11' DARK GREEN Japanese holly, box-leaved holly
Ilex
The genus Ilex, commonly known as holly, is very extensive and includes more than 400 species of evergreen and deciduous shrubs and trees, distributed from the tropics of South America through the subtropics of Asia to the temperate zones of Europe. In addition to the possibility of variegated foliage, their greatest advantage is evergreen character, at least in most species, which makes them an excellent complement to deciduous trees and shrubs during the dormant season. Moreover, many hollies naturally lack spines, which will please those who dislike prickly shrubs. The most horticulturally significant are the East Asian species, among which the Japanese holly (Ilex crenata) stands out. This species was described in 1784 by the Swedish botanist Carl Peter Thunberg (1743–1828) during his stay in Japan.
Japanese hollies are very useful and elegant evergreen shrubs that many people at first glance mistake for boxwoods or honeysuckles because of their small, glossy leaves. This very resemblance has predestined them to become the ideal replacement for true boxwoods, which in Europe are gradually disappearing under the pressure of the massive invasion of the box tree moth and due to the fungal disease known as box blight, which has been devastating plantings especially in the British Isles. Japanese hollies, however, are thornless, offer a wide range of shapes and sizes, and require only minimal care. Since they are naturally quite variable, new mutations and cultivars often appear, each slightly different from the last – and every novelty is, of course, a welcome delight.
DARK GREEN is a Japanese holly variety which says it all in a name. Evergreen, oval leaves are very dark green, handsome, and appear along deep purple red stems. Being a female variety, it produces profusion of small, creamy white flowers in mid spring, followed by abundance of spherical, slightly poisonous, glossy, black berries if pollinated by a male variety from nearby.
It grows about 20-30 cm per year into a well-branched, bushy shrub almost 3m tall and a little less wide. Use it just like a box plant - in the same spot or a container, among other large-leaved, evergreen plants to which its delicate foliage will provide a great contrast, or - if you are patient - make a hedge out of it.
Japanese holly is tolerant of most soil types except heavy clay, but it thrives best in well‑drained, evenly moist, acidic soil, occasionally enriched with slow‑release fertilizer. It has a strong root system that copes better with poorer conditions than English hollies and adapts easily to the limited root space of containers without showing signs of stress or drought. It is hardy to about −27 °C (USDA zone 5) and is also suitable for outdoor planters with good drainage and where it requires more frequent but careful watering, including during frost‑free winter days.
Last update: 17-12-2018
