The majestic tree often referred to as a cedar is an evergreen conifer valued for its fragrance and durability. The term “cedar” is commonly applied to many trees, creating a distinction between true and false cedars. True cedars belong exclusively to the genus Cedrus, which includes the Atlas, Deodar, and Lebanon cedars, all members of the Pine family (Pinaceae). Many popular North American trees, such as the Western Red Cedar (Thuja plicata) or Eastern Red Cedar (Juniperus virginiana), are botanically considered false cedars, belonging instead to the Cypress family (Cupressaceae). This guide focuses on establishing and maintaining true cedars in a landscape setting.
Selecting the Right Species and Site
Choosing the appropriate species for a location is the first step toward successful growth. The Atlas Cedar (Cedrus atlantica) and the Lebanon Cedar (Cedrus libani) are hardy to USDA Zone 6. The Deodar Cedar (Cedrus deodara) thrives best in Zones 7 through 9. Species selection must also account for the tree’s mature size, as true cedars can reach impressive heights and spreads, requiring significant space.
Cedars thrive best in full sunlight, requiring at least six to eight hours of direct sun daily to maintain dense foliage. The ideal planting site should offer well-drained soil, as these trees are susceptible to root rot in waterlogged conditions. A slightly acidic to neutral soil pH, typically between 6.0 and 7.0, is preferred for optimal nutrient uptake.
Before planting, analyze the soil’s composition. If the soil is heavy clay, amend the entire planting area, rather than just the hole, with organic matter like compost or aged bark fines. This improves drainage and aeration. This preparation ensures that the tree’s roots can spread easily into the surrounding native soil, promoting long-term establishment.
Step-by-Step Planting Techniques
Proper planting begins with digging a hole two to three times wider than the root ball but no deeper. Locate the root flare, which is the point where the trunk widens as it meets the root system. This flare must be situated slightly above the surrounding grade, typically one to two inches higher. This height accounts for settling and prevents the trunk from being buried.
For container-grown trees, carefully remove the root ball and gently score or loosen any circling roots to encourage outward growth. If planting a balled-and-burlapped specimen, remove all synthetic materials. Once the specimen is in the hole, cut away the top one-third of any wire basket and all burlap from the sides and top of the root ball. Do not plant the tree on loosened soil at the bottom of the hole, as this will cause it to sink over time.
Backfill the hole with the original soil, tamping gently to eliminate large air pockets. Water thoroughly halfway through the process to settle the soil around the roots. After backfilling completely, apply a two- to three-inch layer of organic mulch, such as wood chips or pine straw, over the entire planting area. Keep the mulch pulled back several inches from the trunk and root flare to prevent moisture buildup and decay.
Essential Long-Term Care
The first year after planting requires consistent, deep watering to encourage a strong root system. Young cedars should receive deep soakings once or twice weekly, allowing the top several inches of soil to dry out between applications. The goal is to saturate the root zone, typically 12 to 18 inches deep, which helps the roots grow downward.
Once established, true cedars exhibit good drought tolerance and require less supplemental water, though they benefit from deep watering during extended dry periods. Fertilization is minimal, as these trees are not heavy feeders. If soil tests indicate a deficiency or if growth is stunted, apply a slow-release, balanced fertilizer, such as a 10-10-10 formulation, in the early spring before new growth begins. Avoid fertilizing after mid-summer, as this can stimulate tender new growth susceptible to early frost damage.
True cedars naturally develop an attractive form and require minimal structural pruning. The primary focus of pruning is the removal of dead, damaged, or diseased branches, which should be done in late winter or early spring. Maintain the tree’s central leader and refrain from cutting back into old wood. Cedars typically do not readily produce new growth from leafless, interior branches.
Managing Pests, Disease, and Environmental Stress
Many health issues in cedars stem from poor site conditions, particularly inadequate drainage, which can lead to fungal problems like root rot. Ensuring the planting site is well-drained and avoiding overwatering are the most effective preventative measures against these pathogens. Fungal needle blights, which cause browning and dieback, are prevalent during periods of prolonged cool, wet weather.
Common insect pests include bagworms, spider mites, and bark beetles, which can cause defoliation or structural damage. Regular inspection allows for early intervention, such as hand-picking bagworms or applying horticultural oil or insecticidal soap to manage spider mites. Preventing drought stress through proper watering helps ward off secondary invaders like bark beetles, which target weakened trees.
Young cedars are vulnerable to environmental stressors, especially winter damage. Windburn and winter sun scald can cause browning of the needles, particularly on the south or southwest sides of the tree. Applying an anti-desiccant spray in late fall or wrapping the trunk with burlap for the first few winters offers protection against extreme temperature fluctuations and excessive moisture loss.