A relative of the flowering dogwood, the aucuba shrub (Aucuba spp.) is also known as Japanese laurel. There are no more than four species of aucuba, all native to eastern Asia, that are grown for their glossy leaves that often bear markings of contrasting colors. Great for shady, dry and salty-aired parts of the landscape as an accent, screen or hedge, the female aucuba shrubs produce red berries that look like those of a holly. Most aucuba shrubs sold at plant nurseries are the species Aucuba japonica.
The amount of direct sunlight tolerated by aucuba shrubs depends on your climate. In cool summer regions, bright shade for no more than eight hours of sun daily is fine. Conversely, where summers are very hot or long, bright shade with indirect light is recommended for no more than four hours of direct sunshine. Also, plants with variegated leaves should not receive as much direct sunlight as those with solid green foliage. If grown as an indoor houseplant, place the container where very bright indirect light and one to two hours of morning or evening sun reaches the foliage.
Plant aucuba plants in any soil that is not soggy or waterlogged after irrigation or rainfall. Tolerant of dry soils and those that are considerably sandy, the shrubs will look and grow better if the soil is fertile and contains organic matter. House plant containers must not be filled with topsoil but with soil-less potting media.
During the growing season, water aucuba freely so the soil remains moist, but never soggy. During the winter months when temperatures are cooler and growth stops, allow soils to become drier and do not over-water. When plants are first planted in the ground, water frequently to keep the root ball moist and to help establish new roots in the surrounding soil. Newly planted shrubs should be monitored and watered as needed to maintain a moist soil at all times for the first six to twelve months. Indoor plants need a slightly moist soil; refrain from over-watering.
From mid-spring to late summer, apply a water soluble well-balanced fertilizer to the shrub once each month. Alternatively, scatter a slow-release granular fertilizer around the root zone of the aucuba to slowly release nutrients for several months. Applying a 3 to 4-inch layer of organic mulch over the root zone in the outdoor garden helps improve soil quality and also decomposes to supply nutrients for use by the plant roots. Do not fertilize in fall or winter months.
Typically aucuba shrubs need minimal pruning, but an occasional errant branch may warrant removal. Prune away any dead or diseased leaves or branches at any time of year. To shear or shape the shrub, it is best to conduct that pruning task in early spring. If you wish to rejuvenate a shrub that is overgrown, leggy or poorly structured, prune back the plant to 12 to 24-inches tall in mid-spring and allow it to grow unimpeded across the summer.
Aucuba shrubs tolerate climates and indoor growing conditions that are no colder than -10 degrees F in winter and where summers provide at least 40 days of temperatures above 86 degrees F. This correlates to U.S. Department of Agriculture winter hardiness zones 6 through 10 and American Horticultural Society heat-zones 12 to 6. Aucuba shrubs in USDA zones 6 and 7 should be shielded from winter winds and drying direct winter sun rays.