Viburnums have long been a popular choice as landscaping shrubs for home gardeners and landscape professionals alike. With their dark green foliage and handsome form, they give the garden a calm, woodsy, refined feel. The dense foliage growing down to the ground makes many species of Viburnum ideal screening plants. They are especially useful as shade hardy plants. There is however, considerable variety amongst the many species and varieties in both their appearance and growing requirements. We will focus here therefore, on one, the Mediterranean native, Laurustinus, known botanically as Viburnum tinus.
This species is hardy to cold down to about -15c, and so is suitable for many climates, not just Mediterranean ones. It grows at a moderate rate to some 3-4 meters (9-12ft) and half as wide. Occasional, light pruning, maintains compact growth and dense foliage. It is better as a screen than as a formally trimmed hedge, as applying the hedge trimmer, bruises and spoils the leaf texture.
Viburnum tinus blooms in the spring with lightly scented white flowers. The flowers are a nice addition to the shrubbery, but not in themselves sufficient reason for growing the plant. The small blue berries though are more visually significant. While they are inedible to us, they attract birds in their droves, which is excellent for effecting a natural pest control, while distracting the birds from the fruit trees in the garden. Laurustinus can therefore be aptly described as decoy plant.
Laurustinus goes well with other landscape bushes of similar foliage texture and growth habit, such as Pittosporum, Feijoa, Myoporum, Raphiolepis, and Coprosma. In frost-free climates, it combines nicely with such shrubs as Duranta erecta, whose fresh, green foliage contrasts interestingly with the Viburnum’s dark leaves, or with the ever-dependable Carissa macropcarpa. It should be noted though, that high humidity is common to mild winter climates, such as coastal regions, a factor that increases the Viburnum’s susceptibility to fungal disease like mildew. It is most successful growing in climates that have dry summers, and cool winters.
Viburnum tinus as a Mediterranean native, can be grown on very little summer irrigation, but will benefit from occasional, deep soakings. This has the positive affect of leaching excessive salts from the soil, to which the species is somewhat sensitive. Its growth can also be stunted by the alkaline conditions typical of many dry climate soils. Adding large amounts of compost and other organic matter to the soil, in addition to its many benefits, lowers the soil’s pH, and thus its alkalinity.