Ilex crenata aka Japanese Holly

Taxonomy

Ilex crenata, also known as Japanese holly or box-leaved holly, is a flowering plant in the Aquifoliaceae family. Native to eastern China, Japan, Korea, Taiwan, and Sakhalin, this evergreen shrub or small tree can reach heights of 3-5 meters (rarely 10 meters) with a trunk diameter of up to 20 centimeters. The glossy dark green leaves are small, measuring 10-30 mm long and 10-17 mm broad, with a wavy margin and sometimes spines. The plants are dioecious, meaning they have separate male and female plants, and produce white, four-lobed flowers. The fruit is a black drupe with a diameter of 5 mm, containing four seeds. Japanese holly thrives in acidic soil with a pH ranging from 3.7 to 6.0. This compact and dense evergreen shrub has glossy dark green foliage. It grows slowly and is a good alternative to boxwood, tolerating pollution well. In spring, small white flowers appear, followed by small black berries in autumn, although some varieties may produce white or yellow berries. Japanese holly plants resemble boxwood and are often used as hedges or foundation shrubs. They can range in height from 3 to 10 feet and have a rounded shape. It's important to choose a cultivar carefully as growth rates can vary. However, it should be noted that Japanese holly is considered invasive in the Lower Hudson Valley.

Common names

Japanese Holly, Box Leaf Holly, Box Leaved Holly

How to care for Japanese Holly

Difficulty

Caring for Japanese Holly is a breeze, as it is highly adaptable and forgiving to minor neglect.

Water

Japanese Holly should be watered regularly, allowing the soil to dry out between waterings.

Soil

Japanese Holly is very sensitive to dry soil. To ensure your Box Leaf Holly is thriving and blooming, choose a potting soil that retains moisture. A good soil should still allow for adequate drainage and contain lots of organic matter. Coco coir or sphagnum moss are great soil additives that will help to retain moisture and provide your Box Leaf Holly with the nutrients it needs for healthy growth. Make sure to mix these soil additives into the potting soil before planting and water the soil thoroughly. By providing your Japanese Holly with a well-draining, moisture-retaining soil, you can help to maximize its growth and keep it blooming.

Lighting

Japanese Holly requires abundant, bright, and direct light to thrive. The best placement for this plant is within one foot of a window to ensure it receives enough light. If you live in an area with more extreme weather, such as hot summers or cold winters, you may need to adjust the placement of the plant accordingly. During hot summer months, it is important to place the plant away from full sun, as this can cause the leaves to yellow or burn. During cold winter months, it is best to move the plant closer to the window to take advantage of the extra light that can help it survive. By keeping an eye on the current weather in your area, you can make sure your Box Leaf Holly is always in the right place to thrive.

Toxicity

Japanese Holly is poisonous if ingested. We suggest keeping this plant out of reach if you have children, cats, or dogs in the home.

Fertilizer

The Japanese Holly grows at a slow pace and doesn't require any supplementary fertilizers. By renewing its potting soil once a year, it should receive enough nourishment. Remember, plants obtain their energy from sunlight, not fertilizers.

Region of origin

Japanese Holly’s native range is E. Asia - China, Japan, Korea.


More info:
Wikipedia