How to Grow and Care for Sky Pencil Holly (A Guide)

Sky Pencil Holly (Ilex crenata) is a narrow, columnar shaped evergreen plant standing like an exclamation point and announcing to all of the passersby due to its conical evergreen shape. 

The first thing about this plant is its name that is named after its narrow pencil-like leaves growing gradually towards the sky. 

The sky pencil is the cultivar of Japanese holly with evergreen foliage that resembles the boxwoods.

Due to its distinctive shape and small tightly packed leaves, this plant is widely used in landscaping and as a hedgerow. It can be grown in the corners and tight spaces of the garden.

Leaves of the holly sky pencil are fairly smooth like boxwoods. The greenish-white coloured flowers grown on this plant are unimpressive but on pollination, it bears the blackberries that attract the birds.

The super-easy growing nature of this plant makes it more attractive to grow. If you have a keen interest in gardening and you want to make your garden an example then the Sky pencil Holly is for you.

They can grow up to the height of 10ft if they are properly maintained and supplied with all the required items like water, sun, and fertilizers. 

It can grow both in soil and in large containers with giving the best look as rising upwards at the outdoor landscape.

Most of the people love to grow them at both sides of the entrance or at the doorway to give an amazing look. 

They can stand out to the wall when arranged in pairs to flank a statue. You can also place them on the decks, patios and foundation plantings.

Sky pencil Holly originally originated from Japan and was introduced to the U.S National Arboretum in 1985. It is part of the boxwood evergreens family.

Growing habit description

Sky pencil grows up to the height of 10ft with its broad top branches that taper towards the bottom. If it is allowed to grow on its own it will not grow more than 2 feet wider at its deepest and it is pruned to get narrower and even. 

Due to its less space covering, it is a great choice for the places where other plants cannot be grown. You may say it as a drawback but it is its nature.

It does not have too many shrubs but offers a great visual appeal that cannot be attained by any other plant with consuming so much less space.

Blooming

The blooms appearing on this plant are very tiny and light green coloured that are very undistinctive and unattractive. 

The same way the leaves of Sky Pencil holly are also tiny, oval and green colored that remains the green whole the year. The main benefit of this holly plant over the others is that it does not have the prickly leaves like the other hollies have. 

After blooming, the berries appearing on the plant is a good food product for the birds and these birds become the addition to your garden. 

As pointed earlier, most people love to grow the Sky Pencil for hedgerows but some other love to plant them as a single shrub in the landscape. If you want to listen to a good statement from visitors then you need to plant the Holy plant separately as it will have its own beauty.

Some persons congested their garden by growing the plants closely and does not allow any plant to express its beauty and colors so many of small or thin plants like holly get ignored.

I don’t think we should plant like these, However, we should provide each plant some space to express and grow naturally.

If you are going to plant the Sky pencil Holly in your garden firstly think about what kind of look you want to get at the end. A long row of bushes of rose with the giant exclamation bushes at the end? Or the proper arranging row of flowers and the two Sky Pencil Hollies bursting through them at the center. 

Besides its beauty, this shrub plant has a number of other benefits. It can be grown around the building to camouflage the unsightly things, rain gutter spots, and the central air conditioning units. 

The Sky pencil Holly has a lifespan of 40 years so you can decide to plant them in your landscape as a long term beauty.

Requirements to grow Sky Pencil

Botanical NameIlex crenata
Common NameSky Pencil holly
Plant TypeEvergreen
Mature SizeCan grow up to 10 feet tall and 2 feet wide
Sun ExposureFull sun, Partial sun
Season of InterestSpring, Summer, Fall, Winter
Soil TypeRich soil that drains well
Soil pHSlightly acidic to neutral
Soil textureWell-drained soil
Water needsAverage
Bloom TimeLate spring
Flower ColorWhite
Hardiness Zones6 to 8
Heat Zones5 to 7

How to Grow Sky Pencil Holly

The sky pencil Holly is a columnar slow-growing shrub that can grow up to the height of 10 feet at its full peak with the width of a small fraction. The width of the holly shrub can spread up to 14 inches when the height of the Sky pencil reaches 6 feet. 

The Sky Pencil Holly can be grown by two methods:

  1. Inground
  2. In containers

The growth of Sky Pencil starts from the propagation and then growing them in-ground or containers as you desire. The planting procedure is described as under.

The shape of Sky pencil Holly is also very impressive that makes it an important plant whenever someone discusses the planting in the landscaping. They have a slow tapering upwards from the bottom making them a tall and thin beauty plant in the landscape. 

Propagation & Cultivation

Sky pencil Holly can be planted outdoors in the areas of the US having the USDA  plant hardiness zones from 6 to 9. In the colder climatic areas, these plants perform well in the containers. 

If you are going to grow them in the container, then you must know that they can be kept outside during the temperate months and then relocate them to a safe area from the snow and cold. 

The green foliage of that plant is super nice at gaze during the season of snow and cold whole around the world. The colours that come from this plant after snow falling are very remarkable. 

The growth speed of this plant is slow but it is very impressive. It seems like the same height every year but it grows slowly and looks like someone is standing ‘at attention’ stance. 

The cuttings of Sky Pencil Holly are locally available at any garden store or online from a store. The sie of the cuttings varies from all suppliers but it does not affect their growth. The only thing to keep in the eye is healthy cuttings. On full growth, after 3 years all will look the same.

Sky pencil Shrubs are the dioecious Plants which means that they have male and female reproductive parts in separate plants. You have to plant at least one male plant to get the berries on the female plant.

1. Growing in the Ground

Planting of Sky pencil Holly is a simple task. When you are going to grow them in the ground, select the soil that has well-drained capacity. For this purpose, the slight sloppy area is a well-chosen.

The Sky Pencil grows well in a wide variety of soil but loves to grow in the slightly acidic soil having moisture keeping ability.

Once you have chosen a place for you Holly bushes, dig up a hole thereto the depth of a root ball with the width of 3 times more than depth. 

The addition of the compost to the soil is a good addition if you want to get proper growth and good soil moisture retention with soil fertility enhancement.

After mixing the compost in the soil put the plant in the soil and cover it firmly with your hands. Now compress the soil around the plant to exclude the air spaces if there are any present in the soil. 

In case you are going to grow the Sky Pencil as the border, you should keep the distance of 2-3 feet between the plants. In this space, these bushes will grow properly without any overcrowding.

After planting the Sky Pencil in the ground the main work just after planting is the watering thoroughly. You should water the plants until they established and begins their growth. 

2. Growing in a Container

From any gardening store, the cuttings of Sky Pencil grown in the container can be obtained. You can simply leave them to grow in the containers and locate them somewhere they could get a good amount of sunlight. 

Due to a slow-growing plant the Sky Pencil will grow well in the container for up to 3 years. After attaining its full height if it seems like that the space in the container is not well enough for the plant to grow next to you should transfer them to a larger one or to the ground as you wish.

During the colder season days, the evergreens are more susceptible to drying out. Due to the low growth of Sky Pencil, they are not completely dormant so you need to ensure that they have adequate moisture in their containers.

care for sky pencil

Basic Requirements to grow the Sky Pencil Holly

Light

Sky Pencil holly is a columnar shrub that can tolerate the shade to some extent but it will grow slower in shade.

This plant performs well in the full sun especially when you re-growing them in the northern areas. Many gardeners in the north conclude to avoid growing of the Sky pencil Hollies On the east and north side of the house.

If you are growing the Holly bushes in the southern areas then you can plant them in partial shade. 

Soil

As discussed earlier this plant performs well in well-fdraied soils. The drainage of the soil can be promoted by adding and well mixing the compost in the soil. 

It prefers the moist soil that should not be too mush moist nor too much dry but slightly acidic.

Water

Watering is a basic need of every plant as it helps the plant to establish a good root system to get their nutrients from the soil. 

Before watering the plants you need to check these things:

  • As a rule of thumb, check the surrounding soil of the plant to make sure that if the soil is dry then water them
  • If the leaves of plant become pale green in color it is the indication that the much moisture is already present in the soil

The Sky Pencil Holly needs the maximum water during the first year of its growth due to the vast root system establishment. After first year Holly Bushes needs water just at the dry spells.

How to increase the moisture retention ability of the soil?

To increase the moisture retention ability of the soil, apply the two to four inches of organic mulch layer on the topsoil and maintain it over the soil as a covering.

Temperature and Humidity

If You are living in the area under zone 5 of temperature, the best practice to plant Sky pencil is in the area that is sheltered from the winds. 

The other best practice in these areas is the mulch application on the soil for moisture retention to help out the plants in summers.

Fertilizer

Fertilization of the Sky pencil Hollies is much easy as it is just a one-time task. Sky Pencil Hollies are fertilized only one time per year. 

The application of fertilizer during the early spring is the best time for Hollie bushes to perform better and get maximum results from the fertilizers.

The Slow-releasing fertilizer or 10-6-4 blend fertilizer is best for the Holly bushes for their growth.

The amount of fertilizer applied per plant is also much concerning part here. One pound of fertilizer per inch of trunk diameter is the recommended dose by the experts for Sky Pencil Hollies. 

Watering after fertilization is the much-needed task so that the fertilizer sink well into the soil.

Pruning of Sky Pencil Hollies

The pruning of Sky Pencil Hollies is not a much-needed task as these plants retain their unique shape if not pruned every time. But if you have planted a row or cluster of holly bushes then you will need to prune them on a regular basis to keep their shape uniform and trimmed well.

The best time for the pruning of bushes is the winter season. You should prune the off branches of the plant that cause the shaggy look. 

To maintain a well-shaped plant, you can also wrap cords or twines around the shrub to pull the branches to the center.

Landscaping of Sky Pencil Hollies

Due to the outstanding beauty of this tall plant, it has become an important part of the landscape industry. 

Sky pencil hollies can be planted these ways in the landscaping as:

  • They can be planted as the privacy barrier in your garden or around your property if they are planted in the rows. These rows will form an attractive look.
  • They can also be planted as separate standing plants as they serve as specimen plants performing vertical interest for the visitors. You can plant them at the entry of the house or the entrance to the driveway.
  • They can also be planted as the foundation plantings at the corners of planting beds as the flowers blooming between these vertical bushes will give a breathtaking scene.
  • They can be planted in portable pots or boxes for patio, porch or terraces.

Other companion plants with Sky pencil hollies

  • Azalea (Azalea)
  • Peony (Paeonia)
  • Blueberry (vaccinium)
  • False Holly (Osmanthus)
  • Astilbe (Astilbe)

Varieties of Sky Pencil Holly

Various varieties of sky pencil Hollies are present in the market that have similar beautification. Some popular are these:

  • Ilex crenata Hetzii
  • Male Pollinator- Beehive (Dwarf variety)

Care for Sky Pencil Holly

When it comes to the care for Sky Pencil Hollies, you need to relax as it needs a little care and maintenance. These plants need some care during the first growth year until they established well.

In your daily busy routine, you will just need to get some free time for pruning if you want to keep them trimmed and small. 

The timely fertilization during the early spring with watering is the basic need of these plants to perform well. 

If you are living in the area having the snowfall in winters then you will need some extra care to keep the branches of the trees from breaking. To protect them tied up a length of twine spiralled from bottom to top then again back to bottom to keep the branches tightly spiralled and protected.

A layer of mulch around the base of plants will help to protect the roots from frosty weather.

Climate

For growing Sky Pencil Hollies the USDA hardiness zones 8 or higher seems best. These plants prefer to grow in full sun but they can also be planted in partial shade so it does not burn.

In the zones of 6 and 7, they can be planted in the full sun but a little bit of shade to get their maximum growth. In these zones, they also need protection from the wind’s strokes.

But in the zones hardiness 5, the planting of Sky pencil Hollies in full sun is best since they receive maximum sunlight on the south and west sides of the building or the house.

Toxicity of Sky Pencil Holly

Every plant has some toxicity to other livings. Some are more poisonous and some are less. The same way SKy Pencil Hollie Berries are too Toxic if swallowed by the pests or children.

Swallowing of the Holly Berries will cause vomiting, diarrhea, and dehydration in the children.

Potential Problems of Sky Pencil Hollies

The incredible thing about this bushy plant is that it rarely comes under the attack of pests or diseases. But you need to get some knowledge to counteract them in case any harms occur.

Pests:

Spider Mites

  These tiny creatures are very hard to see with the naked eye even they live in the form of colonies. But you will come to know them after there attack.  

These pests attacked mostly in the dry and hot climates. They drink the sap of leaves and leaves the marks on the leaves and cause the leaves to dry and yellow and eventually drop off. 

To overcome this problem you do not need to spray the insecticide as it will kill all the beneficial insects too. Instead, trim the damaged leaves from plant to prevent their spread.

The side measure to control this problem is to throw away the debris from the area to control the primary settling of these mites in the area.

Diseases:

Black Rot

This awful disease occurs due to fungal attack and it causes the leaves to turn yellow and eventually drop off. If this fungal attack is not controlled timely it will cause the stems and leaves to die off and stunted growth.

Both the younger and established plants are susceptible to this disease. If the plant start to dropping leaves then it is a sign of too late to control. At that time you need to remove and destroy that plant otherwise this disease will spread to other plants.

This disease can cause the soil to remain toxic for newly planted plants at that place so you need to replace that soil with a healthy one before new planting.

Leaf Spot

this is also a fungal disease and quite similar to root rot on attacking. The difference between this disease and black rot is that the yellow spot appears on the leaf instead of the overall yellowing of leaf in a black rot attack. 

These spots will grow gradually and turn to brown spots and then the leaves will start to fall off and new shoots will also dieoff. 

It can be controlled by applying fungicides every 10 -12 days regularly until the disease ends. Use any best chemical to cope with this disease.

Other Problems

Winter burn

This causes the discolouration of the tips of leaves. As its damage increases the discolouration will move from the tip down further to the leaves at the base of the stem.

The cause of this problem is three overlapping conditions, freezing temperature, high wind, and low moisture. 

To control this white burn, make sure that plants are receiving adequate water. This can be achieved by applying mulch on the topsoil.

Conclusion

Sky Pencil Holly is a dashing plant that is a great addition to your landscape. Its green color and distinctive shape make them a unique part while some landscaper going to establish a new garden or lawn. 

They can be used in versatile as border plants, a statement piece or presentations due to its simplicity and undemanding natural beauty.

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