The African Sumac, scientifically known as Searsia lancea, is a resilient tree for landscapes in arid and semi-arid regions. This evergreen tree is valued for its quick growth rate and graceful, weeping foliage. Native to Southern Africa, it exhibits exceptional drought tolerance, making it an excellent ornamental selection for water-wise gardening. Understanding the specific needs of this species, from initial planting to long-term care, is necessary for successful cultivation.
Site Selection and Environmental Needs
Establishment begins with careful site selection. This species flourishes in full sun exposure, although it can tolerate partial shade, which may result in a slightly slower growth rate. The tree is cold-hardy, thriving in USDA hardiness zones 8 through 11, and handles intense heat well due to its native desert origins.
The African Sumac tolerates poor, rocky, and even highly alkaline soil types. The tree performs best in well-drained conditions, whether the texture is sandy, loamy, or clay-based. Proper drainage is necessary because the tree is highly susceptible to root rot if its roots remain in waterlogged soil, particularly during warmer months.
Consider the tree’s mature size to ensure adequate spacing, as its canopy can reach 20 to 35 feet wide and 20 to 30 feet tall. A minimum distance of 15 feet from permanent structures, such as buildings or patios, is advisable. Planting at least four feet away from hardscapes like sidewalks or curbs is also recommended to prevent future conflicts with its deep root system.
The tree naturally exhibits a multi-trunked, shrub-like growth habit when young. If a single-trunk shade tree is desired, selecting a specimen that has already been trained or planning for early structural pruning is important. Choosing a location that accommodates its eventual broad, rounded canopy shape will ensure the tree develops without the need for excessive corrective pruning later in its life.
Planting Procedures and Initial Establishment
Dig a hole that is two to three times wider than the root ball, but no deeper than the height of the root ball itself. The surrounding soil should be loose to encourage lateral root expansion. Placing the tree at the same level it was in its nursery container, or slightly higher, helps prevent water from collecting around the trunk.
After settling the tree into the hole, backfill with the original soil, tamping lightly to remove large air pockets without compacting the soil excessively. Water the newly planted tree thoroughly and deeply immediately after planting to ensure good contact between the roots and the soil.
During the first six to twelve months, a specific watering regimen is necessary to promote deep root growth. Water deeply but infrequently, allowing the top several inches of soil to dry out between applications. A deep soak encourages the roots to grow downward in search of moisture.
Temporary staking may be needed for young trees, especially those trained to a single trunk, to provide stability against strong winds. If staking is used, ensure the ties are loose enough to allow some trunk movement, which helps the tree develop a strong caliper. Finally, apply a two to three-inch layer of organic mulch, such as wood chips, around the base of the tree, keeping it several inches away from the trunk flare to prevent moisture-related decay.
Mature Tree Maintenance
After establishment, maintenance shifts to a more minimal, long-term approach. The mature tree is highly adapted to arid conditions. Established trees only require occasional, deep irrigation, with soil allowed to dry completely between waterings.
Pruning is primarily done to shape the tree and manage its naturally dense, sometimes weeping canopy. The best time for major structural pruning is during the dormant season in late winter or early spring. Focus on removing any dead, diseased, or crossing branches to improve air circulation and light penetration throughout the crown.
The removal of suckers is important. African Sumac has a high tendency to sucker, and these must be cut back cleanly to their point of origin to maintain a clear trunk and prevent the tree from reverting to a dense, multi-stemmed shrub. Regular thinning of the interior canopy also helps manage the weight of the branches and maintains the tree’s overall structure.
Fertilization is rarely required for a mature African Sumac and can become leggy or susceptible to disease if over-fertilized. If the tree shows signs of nutrient deficiency, such as pale foliage or stunted growth, a single application of a balanced, slow-release fertilizer in the early spring may be beneficial. Excessive water or fertilizer should be avoided, as this encourages lush, soft growth that is less resilient and can lead to root rot issues.