Unique and with a style all its own, Sky Pencil holly (Ilex crenata ‘Sky Pencil’) is a versatile plant with dozens of uses in the landscape. The first thing you’ll notice is its narrow, columnar shape. If left to grow naturally, it grows no more than 2 feet (61 cm.) wide, and you can prune it to just a foot (31 cm.) in width. It is a cultivar (cultivated variety) of Japanese holly and has evergreen foliage that resembles boxwoods more than hollies. Read on to find out how to plant a Sky Pencil holly and how easy it is to care for this interesting plant.
About Sky Pencil Holly
Sky Pencil hollies are narrow, columnar shrubs that grow up to 8 feet (2 m.) tall and 2 feet (61 cm.) wide. With pruning, you can maintain them at a height of 6 feet (2 m.) and a width of just 12 inches (31 cm.). They produce small, greenish flowers and female plants produce tiny, black berries, but neither is particularly ornamental. They are grown primarily for their interesting shape.
Sky Pencil holly shrubs grow well in containers. This allows you to use them as architectural plants to frame a door or entryway or on decks and patios. You don’t have to worry about coming in contact with the plant because the leaves aren’t prickly as with other types of holly shrubs.
In the ground, you can use Sky Pencil holly shrubs as a hedge plant. They come in handy in places where you don’t have room for the width of bushier plants. They look well-groomed without much pruning, and you can use them in formal gardens alongside neatly sheared plants.
Planting and Care of Sky Pencil Hollies
Sky Pencil hollies are rated for USDA plant hardiness zones 6 through 9. They adapt to full sun or partial shade. In zones 8 and 9, provide protection from harsh afternoon sun. In zone 6 it needs protection from strong winds. It grows well in any well-drained soil.
Dig the planting hole as deep as the root ball and two to three times wider. Mix some compost with the fill dirt if your soil is heavy clay or sand. As you backfill the hole, press down with your foot from time to time to remove air pockets.
Water deeply after planting and add more fill dirt if the soil settles. Apply 2 to 4 inches (5-10 cm.) of organic mulch over the root zone to help keep the soil moist and water often until the plant is established and growing. Your new holly won’t need fertilizer until the first spring after planting.
Long-Term Sky Pencil Holly Care
Once established, Sky Pencil hollies need very little care. They don’t need pruning unless you want to maintain them at a shorter height or narrower width. If you choose to prune them, do so in winter while the plants are dormant.
Fertilize Sky Pencil hollies in spring with one pound of 10-6-4 or special broadleaf evergreen fertilizer per inch (2.5 cm.) of trunk diameter. Spread the fertilizer over the root zone and water it in. Established plants need watering only during dry spells.