Japanese holly 'Sky Pencil'
Ilex crenata 'Sky Pencil' · Aquifoliaceae Popular
A very narrow, upright column of small, dark, evergreen leaves, taller than a person and no wider than a doorway.
- Size
- 8 ft tall, 24 in wide
- Zones
- 5 to 8
- Light
- Full sun to part sun
- Flowers
- Grown for its leaves
- Pets
- Toxic (mild)
- Job in a bed
- Accent
A bed built around Japanese holly 'Sky Pencil'
The planner designed this bed around Japanese holly 'Sky Pencil' when this page was made: a 12 × 6 ft (3.7 × 1.8 m) English border in zone 6, full sun. It chose the other plants from the 966 that suit those conditions, and says below why Japanese holly 'Sky Pencil' stands where it does.
The plants
- 1 Japanese holly 'Sky Pencil' × 1, dark green leaves
- 2 Sea thrift × 7, pink
- 3 Leadwort × 19, blue
- 4 False sunflower 'Summer Sun' × 3, yellow
- 5 Beardtongue 'Husker Red' × 3, white
- 6 Calamint × 3, white
- 7 Star of Persia × 2, purple
- 8 Daffodil × 7, yellow
Why this plant
- The only plant grown for its leaves. Leaf lasts all season, where a flower lasts a few weeks.
- The bed's only structure. Shrubs and grasses keep their shape when the perennials die down, and it is the only one here.
Why here
- Anchors a back corner. At 8 ft it is the tallest plant here, and the tallest close the ends of the bed, where they stand in front of nothing.
- A step in the back row. Next to beardtongue 'Husker Red' (2½ ft): no two neighbours there are the same height, so the back steps up and down like a skyline.
- One plant, alone. A shrub is seen as an object, and needs clear ground around it.
Why now
- Here for its leaves, all year. They cover the 14 weeks between early March and late November when nothing on the plan is in flower.
- One of two evergreens. They are what the bed has to show from November to March.
Planned as an English border: 5 of the 6 groups (83%) are drifts, longer along the bed than they are deep. The scheme leans cool (pink, blue and purple) and uses yellow for warmth, with white to calm things between them. The bed is tied together by its repeats: two kinds come round again along it, leadwort and sea thrift. The Design check says heights needs revision.
The planner's own design check: 12 Excellent, 4 Good, 1 Needs revision. Its weakest point is height and scale: Heights average about 10 in at the front, 18 in in the middle and 4 ft at the back. Along the back row the heights step up and down, between 2½ ft and 8 ft, and no two neighbours are the same height. It flags one thing to watch: Nothing on this plan is highly poisonous or an aggressive spreader.
Open this bed in the planner Change its size, the sun or the style, move plants about, or swap one for another.
Where Japanese holly 'Sky Pencil' goes in a border
At 8 ft it belongs at the back of a bed. In the planner's ten height classes it is super tall (over 6½ ft).
Its job: accent. An upright plant used singly, like a punctuation mark, and repeated at intervals to give the bed rhythm.
An evergreen exclamation mark that takes up almost no ground. One marks a corner; a pair frames a door or a path. Tie it loosely in snowy climates, so that snow does not splay the stems.
- Vertical accents in tight spaces
- Flanking an entrance
- Formal containers
What to plant with Japanese holly 'Sky Pencil'
Plants recorded as good partners for it, and what each pairing does:
- Boxwood 'Green Velvet': low enough (3 ft) to stand in front of it.
- Catmint 'Walker's Low': adds the flowers, mid May to mid September; low enough (24 in) to stand in front of it.
- Cranesbill 'Rozanne': adds the flowers, early June to early October; low enough (18 in) to stand in front of it.
Questions about Japanese holly 'Sky Pencil'
Does Japanese holly 'Sky Pencil' need sun or shade?
Japanese holly 'Sky Pencil' grows in full sun (6 or more hours of direct sun a day) and part sun (4 to 6 hours of sun, including some afternoon sun).
It wants ordinary well-drained soil, of average fertility, and a good soak in dry spells. Once settled in, it stands drought.
What zones does Japanese holly 'Sky Pencil' grow in?
USDA zones 5 to 8. It is hardy to zone 5, which means it survives winter nights down to about −10 °F (−23 °C).
Above zone 8 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.
Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.
How far apart should Japanese holly 'Sky Pencil' be planted?
24 in (60 cm) apart, from the middle of one plant to the middle of the next. That is about its full width, so each plant keeps its own outline.
It grows 8 ft (240 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.
How many Japanese holly 'Sky Pencil' plants do I need?
At 24 in apart, set out in staggered rows:
- 3 to fill 10 square feet (about 1 m²)
- 6 for a single row 10 ft (3 m) long
- 10 to fill a 4 × 8 ft bed on its own
In a mixed border, plant it as one at a time, repeated along the bed at intervals; a slender one reads better as a clump of three.
In the bed above, the planner used one in one group.
Is Japanese holly 'Sky Pencil' poisonous to dogs and cats?
Yes: mild toxicity to people, dogs, cats and horses. The berries and leaves cause vomiting and diarrhoea if eaten.
Rated from NC State Extension. Where references disagree, the more cautious rating is used.
Is there a pet-safe plant like Japanese holly 'Sky Pencil'?
These come closest to doing what Japanese holly 'Sky Pencil' does, and no toxicity is recorded for them:
- Juniper 'Gold Cone': the same job in a bed; 24 in shorter, 4 in narrower.
- Dwarf Alberta spruce: the same job in a bed; 16 in wider.
- Arborvitae 'Degroot's Spire': the same job in a bed; 3½ ft taller, 8 in wider.
Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.
Do deer eat Japanese holly 'Sky Pencil'?
Mostly not. NC State lists it as resistant to deer. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.
What does Japanese holly 'Sky Pencil' look like in winter?
Japanese holly 'Sky Pencil' keeps its dark green leaves all winter, so it is one of the plants that hold a bed together from November to March, when the perennials have gone.
Is Japanese holly 'Sky Pencil' good for bees and butterflies?
Japanese holly 'Sky Pencil' is visited by pollinators, bees and specialist bees.
More Ilex
- Blue holly Ilex x meserveae
- Blue holly 'Blue Princess' Ilex x meserveae 'Blue Princess'
- Burford holly Ilex cornuta 'Burfordii'
- Dwarf yaupon holly Ilex vomitoria 'Nana'
- Inkberry Ilex glabra
- Inkberry 'Gem Box' Ilex glabra 'SMNIGAB17' (Gem Box)
- Inkberry 'Shamrock' Ilex glabra 'Shamrock'
- Japanese holly 'Helleri' Ilex crenata 'Helleri'
- Japanese holly 'Soft Touch' Ilex crenata 'Soft Touch'
- Winterberry Ilex verticillata
- Winterberry 'Berry Poppins' Ilex verticillata 'FARROWBPOP' (Berry Poppins)
- Winterberry 'Red Sprite' Ilex verticillata 'Red Sprite'
- Winterberry 'Winter Red' Ilex verticillata 'Winter Red'
In these guides
Every fact on record
- Type
- Shrub
- Size
- 8 ft (240 cm) tall, 24 in (60 cm) wide
- Plant
- 24 in (60 cm) apart
- Height class
- Super tall (over 6½ ft)
- Place in the bed
- Back
- Flowers
- None: grown for its foliage
- Leaves
- Fine texture, evergreen; dark green
- Shape
- Upright, clumping
- Hardy in
- USDA zones 5 to 8
- Light
- Full sun, part sun
- Soil
- Average, well-drained
- Water
- Moderate
- Feeding
- Light, in spring
- Family
- Aquifoliaceae
- Comes from
- East Nepal to Temperate East Asia, Japan and Korea
- Attracts
- Pollinators, bees, specialist bees
- Stands up to
- Deer, drought, pollution
Checked against NC State Extension. Flowering times are for zone 5: later in colder zones, earlier in warmer ones. Toxicity and spread information is a general gardening guide, not veterinary or medical advice, and invasive status varies by region. If a person or pet eats a plant, contact poison control or a vet. Check your local invasive species list before planting anything with a spread warning.