Emerald Green Arborvitae (Thuja occidentalis ‘Smaragd’) is a popular evergreen, recognized for its narrow, pyramidal form and vibrant green foliage that maintains its color year-round. It is widely used for privacy screens, defining property lines, or as an accent in landscapes. The long-term success of this conifer depends on proper planting, with timing a primary consideration.
Optimal Planting Seasons for Emerald Green Arborvitae
The most favorable times to plant Emerald Green Arborvitae are during the spring and fall seasons. Planting in early to mid-spring, after the last hard frost but before intense summer heat, provides an ideal window. This allows the plant to establish its root system in warming soil without immediate stress. Similarly, late summer to early fall, when daytime temperatures moderate and before the ground freezes, offers another excellent opportunity. During this time, the soil retains warmth from summer, promoting root growth, while cooler air temperatures reduce moisture loss from foliage. Both spring and fall planting windows offer moderate temperatures and consistent moisture availability, conducive to successful root establishment.
Understanding Why Planting Timing is Crucial
Moderate temperatures in spring and fall minimize transplant shock for newly planted Emerald Green Arborvitae. Transplant shock occurs when a plant experiences stress from being moved, often manifesting as wilting or stunted growth. Cooler air temperatures reduce water evaporation from the plant’s needles, while warm soil encourages new root development. Soil temperature is a factor, as root growth is most efficient above 45-50°F (7-10°C). Planting in spring or fall ensures the soil is within this optimal range, allowing roots to actively grow before environmental extremes.
Planting during peak summer can lead to severe heat stress and excessive water demand. Conversely, planting in winter, especially when the ground is frozen, prevents new root growth and can expose the plant to desiccation from cold winds.
Preparing for Successful Emerald Green Arborvitae Planting
Preparation before and during planting is important for the long-term health of Emerald Green Arborvitae. Select a site that receives full sun to partial shade, meaning at least six hours of direct sunlight daily for optimal growth. The soil should be well-draining, as these plants do not tolerate standing water, which can lead to root rot.
Before planting, assess the existing soil and amend it if necessary to improve drainage or nutrient content. For heavy clay soils, incorporating organic matter such as compost can enhance aeration and drainage.
Dig the planting hole two to three times wider than the root ball, but only as deep as the root ball itself. The top of the root ball should be level with, or slightly above, the surrounding soil grade to prevent water from pooling around the trunk.
Carefully remove the arborvitae from its container, gently loosening any circling or matted roots. Place the plant in the center of the hole, ensuring it stands upright, then backfill with excavated soil, gently tamping down to remove large air pockets. Avoid burying the trunk too deeply, as this can lead to bark decay and overall plant decline.
Essential Post-Planting Care
Immediate and consistent watering is important after planting Emerald Green Arborvitae to help settle the soil and eliminate air pockets. Provide a thorough initial soaking, allowing water to penetrate deeply. Establish a regular watering schedule, particularly during the first year, for successful establishment.
During dry periods, supplemental watering is necessary to keep the soil consistently moist but not waterlogged. Deep, infrequent watering is generally preferred over shallow, frequent watering, as it encourages roots to grow deeper.
Applying a two to three-inch layer of organic mulch, such as shredded bark or wood chips, around the base helps retain soil moisture, regulate soil temperature, and suppress weed growth. Ensure the mulch does not directly touch the trunk, leaving a small gap to prevent moisture buildup and potential rot.
Monitor the plant for signs of stress, such as browning needles or wilting, and address pests or diseases promptly. Proper aftercare contributes to the plant’s ability to establish a robust root system and thrive in its new environment.