Japanese holly (inutsuge) Ilex crenata
Japanese holly (inutsuge) (Ilex crenata) is an evergreen perennial shrub in the Aquifoliaceae family, native to Japan, Korea, eastern China and Sakhalin. It grows 1–4 m (3.3–13 ft) tall and 1–3 m (3.3–10 ft) wide, wants part sun to part shade and moderate water, and is hardy to about -23 °C (-9 °F). Space plants about 60 cm (24 in) apart.
Plan Japanese holly (inutsuge) in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Japanese holly (inutsuge) at a glance
| Type | Perennial shrub, evergreen |
|---|---|
| Family | Aquifoliaceae |
| Mature height | 1–4 m (3.3–13 ft) |
| Mature spread | 1–3 m (3.3–10 ft) |
| Spacing | 60 cm (24 in) centre to centre |
| Sun | Part sun to part shade, at least 3 h of direct sun a day |
| Water | Moderate; drought tolerance low, waterlogging tolerance low |
| Soil pH | 4.5–6.5 |
| Cold hardiness | About -23 °C (-9 °F) once established (roughly USDA zone 6) |
| Heat stress | Likely above about 34 °C (93 °F) |
| Flowering | from about May for 2–3 weeks (northern hemisphere; later in cold climates, earlier in warm ones) |
| Wind tolerance | Moderate |
| Pollinator value | Moderate |
| Edible | Not grown as food |
| Native to | Japan, Korea, eastern China and Sakhalin |
| Common in gardens of | 🇯🇵 Japan, 🇰🇷 South Korea, 🇨🇳 China, 🇺🇸 United States, 🇬🇧 United Kingdom, 🇩🇪 Germany, 🇳🇱 Netherlands, 🇨🇦 Canada |
| Invasive in | mid-Atlantic United States: check local rules before planting |
Is Japanese holly (inutsuge) toxic?
- People: mildly toxic
- Cats: mildly toxic
- Dogs: mildly toxic
- Parts: berries
Holly berries contain saponins: vomiting and diarrhoea if eaten (ASPCA lists hollies as toxic).
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Japanese holly (inutsuge)
No well-documented helpful pairing. Group it with plants that like part sun to part shade and moderate water.
Questions about Japanese holly (inutsuge)
- How far apart should I plant Japanese holly (inutsuge)?
- About 60 cm (24 in) apart, centre to centre. A mature plant spreads 1–3 m (3.3–10 ft).
- Does Japanese holly (inutsuge) need full sun?
- Part sun to part shade: at least 3 hours of direct sun a day.
- How much water does Japanese holly (inutsuge) need?
- Moderate water. Drought tolerance is low and waterlogging tolerance low.
- How cold-hardy is Japanese holly (inutsuge)?
- It tolerates about -23 °C (-9 °F) once established, roughly USDA zone 6.
- When does Japanese holly (inutsuge) flower?
- From about May for 2–3 weeks (northern hemisphere; later in cold climates, earlier in warm ones).
- Is Japanese holly (inutsuge) poisonous to cats and dogs?
- For cats it is mildly toxic; for dogs mildly toxic; for people mildly toxic. Holly berries contain saponins: vomiting and diarrhoea if eaten (ASPCA lists hollies as toxic).
- What grows well with Japanese holly (inutsuge)?
- There is no well-documented companion pairing for Japanese holly (inutsuge). Group it with plants that like the same sun (part sun to part shade) and water (moderate).
Sources and evidence
Evidence grade B (B: extension service or peer-reviewed).
- Missouri Botanical Garden Plant Finder, Missouri Botanical Garden
- Extension Gardener Plant Toolbox, NC State Extension
- ASPCA Toxic and Non-Toxic Plant List, ASPCA
Notes and assumptions
- Tiny glossy leaves and black berries; clipped into the rounded mounds (karikomi) of Japanese gardens and used in Europe as a box substitute, since it does not get box blight.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- English holly Ilex aquifolium
- Winterberry holly Ilex verticillata
- Yerba mate Ilex paraguariensis
- Bigleaf hydrangea Hydrangea macrophylla
- Rhododendron Rhododendron
- Boxwood Buxus sempervirens
- Oleander Nerium oleander
- Common ninebark Physocarpus opulifolius