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Ilex crenata 'Sky Pencil'

Phonetic Spelling
EYE-leks kre-NAH-tuh
This plant has low severity poison characteristics.
See below
Description

The sky pencil holly is a female cultivar of Ilex crenata, Japanese Holly, a native of Japan and east Asia that can be found in thickets, woods and wet places in lowland and mountains all over Japan. Sky Pencil Holly is a handsome evergreen shrub that is smaller that most of the species at 6 to 8 feet high, is densely branched, tight, and has columnar growth. It has a fastigiate form, meaning narrowing toward the top and having upright, usually clustered, branches that it maintains without pruning. It is a good container or accent plant and works well in formal gardens as it provides a good vertical accent in mixed borders. The Sky Pencil Holly was voted Holly of the Year for 2004 by the Holly Society of America.

Sky Pencil Holly is easy to transplant and urban tolerant. Plant in the full sun to partial shade in acidic well-drained soil though it tolerates a wide range of soil types, from moist to dry, and actually prefers clay. It tolerates shade and air pollution. However, it does not do well in alkaline soils or under drought conditions. It does have a slow growth rate and it may not thrive in areas with high heat and humidity (USDA zones 8 and 9). The species is dioecious (meaning individual flowers are either male or female, but only one sex is to be found on any one plant, thus both male and female plants must be grown if seed is required). It is pollinated by bees and is not self-fertile. Sky Pencil Holly is an all-female cultivar which needs a male pollinizer in order to produce fruit.

Diseases, Insect Pests, and Other Plant Problems:

This plant needs protection from the wind and cold with a wind break and mulching. Spider mites and nematodes are occasional pests.  Alkaline soils will cause the leaves to yellow.

The Clemson Cooperative Extension Home and Garden Information Center has a factsheet on common diseases and insect pests.

More information on Ilex crenata.

See this plant in the following landscape:
Cultivars / Varieties:
Tags:
#small tree#full sun tolerant#shrub#dark green#mixed borders#columnar#easy to transplant#glossy leaves#formal garden#border planting#black fruits#urban conditions tolerant#clay soils tolerant#partial shade tolerant#stormwater demo garden orange co#accent
 
Cultivars / Varieties:
Tags:
#small tree#full sun tolerant#shrub#dark green#mixed borders#columnar#easy to transplant#glossy leaves#formal garden#border planting#black fruits#urban conditions tolerant#clay soils tolerant#partial shade tolerant#stormwater demo garden orange co#accent
  • Attributes:
    Genus:
    Ilex
    Species:
    crenata
    Family:
    Aquifoliaceae
    Life Cycle:
    Woody
    Recommended Propagation Strategy:
    Seed
    Stem Cutting
    Country Or Region Of Origin:
    East Nepal to Temperate East Asia, Japan and Korea
    Fire Risk Rating:
    medium flammability
    Wildlife Value:
    The small fragrant flowers attract bees. Members of the genus Ilex support the following specialized bee: Colletes banksi.
    Play Value:
    Wildlife Food Source
    Particularly Resistant To (Insects/Diseases/Other Problems):
    Mildly resistant to damage by deer.
    Edibility:
    Use caution. Human ingestion of berries can cause minor toxic reaction.
    Dimensions:
    Height: 4 ft. 0 in. - 10 ft. 0 in.
    Width: 1 ft. 0 in. - 3 ft. 0 in.
  • Whole Plant Traits:
    Plant Type:
    Shrub
    Woody Plant Leaf Characteristics:
    Broadleaf Evergreen
    Habit/Form:
    Columnar
    Dense
    Erect
    Multi-stemmed
    Growth Rate:
    Slow
    Maintenance:
    Medium
    Texture:
    Medium
    Appendage:
    Spines
  • Cultural Conditions:
    Light:
    Full sun (6 or more hours of direct sunlight a day)
    Partial Shade (Direct sunlight only part of the day, 2-6 hours)
    Soil Texture:
    Clay
    Loam (Silt)
    Sand
    Soil pH:
    Acid (<6.0)
    Neutral (6.0-8.0)
    Soil Drainage:
    Good Drainage
    Moist
    Occasionally Wet
    Available Space To Plant:
    3 feet-6 feet
    6-feet-12 feet
    USDA Plant Hardiness Zone:
    5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b
  • Fruit:
    Fruit Color:
    Black
    Fruit Value To Gardener:
    Showy
    Display/Harvest Time:
    Fall
    Winter
    Fruit Type:
    Berry
    Drupe
    Fruit Length:
    < 1 inch
    Fruit Width:
    < 1 inch
    Fruit Description:
    Black, globose, berrylike-fruit on pollinated female plants from fall to winter that are 1/4 inch in length. Fruits are hidden below the foliage. Sky Pencil Holly cultivars are all female, thus a male cultivar is required nearby for pollination.
  • Flowers:
    Flower Color:
    Green
    White
    Flower Inflorescence:
    Cyme
    Flower Value To Gardener:
    Fragrant
    Flower Bloom Time:
    Spring
    Flower Petals:
    4-5 petals/rays
    Flower Size:
    < 1 inch
    Flower Description:
    Small (1/4 inch), dull, greenish white fragrant flowers in spring that form in clusters of 1 to 3. Pistillate cyme, in leaf axils of current season's growth; staminate solitary in leaf axils of current season's growth.
  • Leaves:
    Woody Plant Leaf Characteristics:
    Broadleaf Evergreen
    Leaf Color:
    Green
    Leaf Feel:
    Glossy
    Leaf Value To Gardener:
    Long-lasting
    Leaf Type:
    Simple
    Leaf Arrangement:
    Alternate
    Leaf Shape:
    Ovate
    Hairs Present:
    No
    Leaf Length:
    < 1 inch
    Leaf Width:
    < 1 inch
    Leaf Description:
    Leaves are alternate, glossy, dark green, slightly convex, and 1 3/8 inches long and 3/4 of an inch wide.
  • Bark:
    Bark Color:
    Dark Gray
    Surface/Attachment:
    Smooth
    Bark Description:
    Smooth, gray-brown or slightly greenish.
  • Stem:
    Stem Color:
    Green
    Stem Is Aromatic:
    No
    Stem Surface:
    Hairy (pubescent)
    Stem Description:
    Stems are green on current season growth, and turn gray-green to gray-brown by year 2 or 3. They are often densely pubescent on young stems. Dense and rigid at maturity.
  • Landscape:
    Landscape Location:
    Container
    Patio
    Walkways
    Landscape Theme:
    English Garden
    Winter Garden
    Design Feature:
    Accent
    Border
    Attracts:
    Bees
    Pollinators
    Specialized Bees
    Resistance To Challenges:
    Pollution
  • Poisonous to Humans:
    Poison Severity:
    Low
    Poison Symptoms:
    Minor toxicity. Ingestion may cause vomiting, diarrhea, or other illness in humans.
    Poison Toxic Principle:
    Saponins
    Causes Contact Dermatitis:
    No
    Poison Part:
    Fruits