Thuja occidentalis ‘Rheingold’ (American Arborvitae)

Thuja occidentalis ‘Rheingold’ is a versatile, attractive conifer that adds a splash of color to the landscape throughout the year. Its manageable size and unique coloring make it a favorite among gardeners looking for a low-maintenance yet visually appealing plant.

Thuja occidentalis ‘Rheingold’: An In-depth Look

Thuja occidentalis ‘Rheingold’ is a striking ornamental shrub known for its vibrant foliage and compact growth habit.

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 dwarf coniferous shrub, featuring a dense, rounded habit in youth, becoming more conical as it matures. It’s often chosen for its slow-growing, compact nature, making it an excellent choice for smaller landscapes.

Size: ‘Rheingold’ typically reaches about 3-5 feet in height and a similar spread (90-150 cm), making it a moderately sized plant suitable for various garden settings.

Foliage: The foliage is its standout feature, with vibrant golden-yellow leaves that can turn to a coppery hue in the winter. The leaves are scale-like and closely arranged, giving the plant a dense, textured appearance.

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

Uses: ‘Rheingold’ is popular in landscape design for foundation plantings, specimen planting, rock gardens, and as a part of mixed borders. It’s also suitable for container gardening due to its modest size.

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: It offers year-round visual interest with minimal maintenance requirements.

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.