Thuja occidentalis ‘Holmstrup’ (American Arborvitae)

Thuja occidentalis ‘Holmstrup’ is an excellent choice for gardeners looking for a compact, upright evergreen with low maintenance needs. Its narrow form and vibrant green foliage make it a standout plant for a variety of landscaping purposes.

Thuja occidentalis ‘Holmstrup’: An In-depth Look

”Holmstrup’ is a cultivar of Thuja occidentalis (Eastern Arborvitae) known for its upright, narrow, and columnar growth habit. It’s prized for its dense, rich green foliage and compact form, making it a popular choice for landscaping.

Native: Thuja occidentalis is native to North America. It is predominantly found in the northeastern United States and southeastern Canada. This species naturally occurs in wet forests, swamps, and along lake shores, thriving in cool, moist, well-drained environments.

Plant Type and Habit: This is a coniferous evergreen shrub, characterized by its tight, columnar shape. It maintains its form naturally, requiring minimal pruning.

Size: Slow-growing, about 8-12 inches per year (20-30 cm), ‘Holmstrup’ typically reaches a height of 6-10 feet (180-300 cm) and a spread of about 2-3 feet wide (60-90 cm) after 10 years, eventually maturing to 10-15 feet tall (300-450 cm) and 3-5 feet wide (90-150 cm) at maturity.

Foliage: The foliage consists of small, scale-like leaves that are a deep, lustrous green. The leaves are densely packed, creating a thick and lush appearance.

Bark: The bark is reddish-brown, relatively smooth, and becomes more textured with age.

Uses: Ideal for use in hedges, privacy screens, or as a standalone specimen. Its narrow growth makes it perfect for tight spaces, formal gardens, or as an accent in mixed borders.

Award: Recipient of the prestigious Award of Garden Merit< of the Royal Horticultural Society.

Hardiness: Hardy in USDA zones 3-7, it can withstand cold winters and a range of environmental conditions.

Wildlife: Provides limited shelter for small wildlife.

Toxicity: Generally considered non-toxic to humans and animals.

Deer and Rabbit: May suffer some damage from deer and rabbits, especially in areas where these animals are prevalent.

Invasiveness: This cultivar is not considered invasive and typically stays within its planted boundaries.

Benefits: Offers the benefits of a compact, upright growth habit, making it versatile for various landscaping needs. It’s low-maintenance and provides year-round greenery and structure in the garden.

American Arborvitae Growing Tips

Light: Thrives in full sun but can also grow well in partial shade. Full sun exposure leads to denser foliage growth. Usually appreciates some light afternoon shade in hot summer climates. Protect from drying winds, especially when young.

Soil: Adaptable to a wide range of soils but prefers moist, well-drained, slightly acidic to neutral soil. Tolerates clay soils.

Water: Regular watering is important, especially for young plants and in dry conditions. Avoid extreme dry soil in the fall, which can cause the evergreen foliage to dry out in winter.

Fertilizer: Apply a balanced, slow-release fertilizer in early spring. Over-fertilization can harm the plant, so follow the recommended rates.

Pruning: Little to no pruning is required. Prune for shaping or size control in late winter or early spring before new growth starts. Avoid heavy pruning.

Mulch: Provide a generous root zone mulch.

Propagation: Propagated through semi-hardwood cuttings in late summer.

Pests and Diseases: Watch for bagworms, spider mites, mealybugs, and scale insects. Leaf tips may suffer damage from leaf miners. Canker can sometimes pose a problem. Fungal diseases like root rot can occur in poorly drained soils. Good air circulation and proper planting depth help prevent these issues.