Sky Pencil holly, in the Ilex genus, is a stunning architectural shrub that is suitable for borders, entry accent points, containers and focal specimens. It is a slender shrub that is easy to sneak into smaller spaces and adds dimension and texture. The leaves are much smaller and less cut than the American or European holly trees but it is of the same genus. This cultivar will do well in slightly acidic soils in either sun or shade. It requires little special care and will achieve a natural slim columnar shape without any pruning.
Perform a soil test before you plant to ensure that the pH is acidic enough for Sky Pencil holly. Base or neutral pH is 7, and anything below is gradually more acidic. Sky Pencil will do well in soils with a pH of 6 to 6.5.
Choose either a sunny location or a partially shady area. Sky Pencil is female and will not get flowers unless a male holly is introduced, so sun exposure is not as important as it is on flowering hollies. In the garden, increase the drainage by adding 2 to 3 inches of sand and working it into the planting area to a depth of 12 inches.
Measure the area if you are creating a hedge or border with the plant. This will tell you how many hollies to purchase. Sky Pencil only gets 1 to 3 feet wide but will need a couple of inches between plants for air circulation.
Plant a pair of Sky Pencil hollies at the entrance to a pathway, garden zone, front entry, base of the driveway or any other area that you would like to highlight. Sky Pencil grows slowly, but its easy culture and 10-foot height make it an ideal plant for specimen and accent planting.
Plant a Sky Pencil holly in a container. Choose a container that is nearly twice as deep as the existing root ball since holly will grow a deep tap root. Use a planting mix of 2 parts potting soil, 1 part sand and 1 part peat to enhance the acidity of the soil. Plant a Sky Pencil as deep as it was growing in the nursery container.
Water container and ground plantings thoroughly at installation. In containers, water until it seeps out the drainage holes. In the ground, irrigate until puddles form. Water at least twice a week for the first two weeks and then gradually diminish to once a week. Once established, keep the soil moist to a depth of 3 inches.
Fertilise annually in spring with 0.227kg. of balanced acid lover's fertiliser mixed into the top 3 inches of soil. Water completely after application to prevent root burn. Mulch around the Sky Pencil in United States Department of Agriculture zone 5. It is suitable up to zone 7 but is not hardy below zone 5. Sky Pencil prefers temperate garden zones.