American arborvitae Thuja occidentalis 'Danica'

Water

Arborvitae 'Danica' should be watered deeply and thoroughly to ensure the root ball is moistened. In the first growing season, water the plant once or twice a week depending on the weather conditions, more frequently during hot and dry spells. Once established, the plant is somewhat drought-tolerant but will benefit from watering every two to three weeks, with more frequent watering required in extreme heat. Provide about 1-2 gallons of water per week during the first year, and adjust as necessary as the plant gets established. Avoid overwatering as it can lead to root rot.

Light

Arborvitae 'Danica' thrives best in full sun to partial shade. It should be planted in an area where it will receive at least four to six hours of direct sunlight each day. While it can tolerate shade, too much shade can lead to sparse foliage and a less robust plant. Choose a spot without heavy shade to encourage dense and healthy growth.

Temperature

Arborvitae 'Danica' is hardy and can tolerate a wide range of temperatures. It grows best in temperatures between 40 to 75 degrees Fahrenheit but can survive temperatures as low as -40 degrees and as high as 80 degrees Fahrenheit. To ensure the best growth and health, avoiding extreme temperature fluctuations is important.

Pruning

Arborvitae 'Danica' requires minimal pruning, primarily to shape the plant or remove any damaged or diseased branches. The best time for pruning is in the early spring before new growth begins, or in the late spring after the new growth has hardened off. Annual light pruning helps maintain its globe-like shape and encourages lush, healthy foliage.

Cleaning

Not needed

Soil

The American Arborvitae 'Danica' (Thuja occidentalis 'Danica') thrives best in moist, well-drained soil with a slightly acidic to neutral pH, ideally between 6.0 and 8.0. A good soil mix may include garden soil, compost, and peat moss to ensure adequate drainage and fertility.

Repotting

American Arborvitae 'Danica' does not require frequent repotting and can go several years without being disturbed due to its slow growth rate. It is typically repotted only when it outgrows its current container or when the soil quality degrades.

Humidity & Misting

American Arborvitae 'Danica' is quite adaptable and can tolerate a wide range of humidity levels, but it performs best in moderate to high humidity conditions. It is resilient and does not require specific humidity adjustments when grown outdoors.

Suitable locations

• Indoor

  Place 'Danica' in bright light, avoid dry air and water soil regularly.

• Outdoor

  Plant 'Danica' in full sun to partial shade, and in well-drained soil.

• Hardiness zone

  2-7 USDA

Life cycle

The life cycle of Thuja occidentalis 'Danica', commonly known as American arborvitae 'Danica', begins with seed germination, where the seeds require a period of cold stratification to break dormancy. Once germinated, the seedlings establish themselves and enter a juvenile vegetative phase, growing into small bushes with their characteristic evergreen, scale-like leaves. As they mature, these shrubs enter a reproductive phase, developing small cones that carry their seeds—pollination is typically by wind, with male and female cones often on the same plant. After reaching maturity, these shrubs can reproduce annually, with cones maturing in one year and releasing seeds in late summer or fall. The lifecycle stages repeat annually, with these shrubs having the potential for long lifespans, often living several decades if conditions are favorable. Over time, they may reach a senescence phase, where growth slows and they become less vigorous, ultimately leading to the end of the plant’s life cycle.

Propogation

• Propogation time

  Spring-Early Summer

• The most common method of propagating Thuja occidentalis 'Danica', commonly known as American arborvitae 'Danica', is through semi-hardwood cuttings. This is typically done in late summer. You would take cuttings of the plant's current year growth, making sure they are about 4 to 6 inches (approximately 10 to 15 centimeters) long. The bottom inch of the cutting should be stripped of needles, and the cut end can be dipped in a rooting hormone to encourage root development. Then, the prepared cutting is placed in a well-draining rooting medium, such as a mix of peat and perlite, and kept in a humid, shaded area until roots have developed, which usually takes several weeks. It is important to maintain consistent moisture during the rooting process but avoid waterlogging the medium.