Problems With Otto Luyken Laurel
Cherry laurel cultivar Prunus laurocerasus "Otto Luyken" is a medium-sized, evergreen shrub often used as foundation plantings and hedges in U.S. Department of Agriculture plant zones 6 through 8. The leaves point upward and are dark green on top and pale underneath. In late spring, the plants are covered in fragrant, white flowers. Otto Luyken grows well in sun or shade, and presents only a few problems for gardeners.
Otto Luyken laurel flowers profusely, even in heavy shade, and the white flowers are heavily scented. The sweet scent draws bumblebees to the plant, so use the plant with caution near children's play areas. In addition, the fragrance is heavy enough to bother people sensitive to perfumes and other strong scents.
All cherry laurels require excellent drainage and will decline in heavy, poorly-drained soil. If the soil remains wet, root rot will infect the plant. If the stem of the plant near the soil line is soft and black, the shrub is doomed, as there's no chemical cure for root rot. In heavy soils, plant Otto Luyken on a slope or mound to improve drainage, and make sure that mulch doesn't lay directly against the plant stem. Avoid planting Otto Luyken near downspouts.
Otto Luyken is disease-resistant, but two fungal diseases occasionally bother cherry laurels. The first are Botryosphaeria, a genus of fungi that cause individual branches to die out. The second is Coryneum blight, known as "shot hole," which leaves circular holes in the leaves. Both diseases thrive in cool, moist weather. Don't use overhead sprinklers to water your shrubs, and if either disease is found, treat the plants with a fungicide.
Otto Luyken typically grows 3 to 4 feet tall and 6 to 8 feet wide, but older specimens can reach up to 6 feet tall. If pruning is necessary, you'll find using a hedge clipper just results in a mass of raggedy leaves with brown edges. Instead, use hand pruners and trim back individual stems. Cherry laurels are fast growers, so pruning is a tedious job if you've planted a large number of shrubs. Plan ahead and site them where an extra foot or two of height won't be a problem.