Japanese aucuba (Aucuba japonica) is an evergreen shrub that grows 6 to 10 feet (2-3 m.) tall with colorful, green, and yellow-gold leaves as much as 8 inches (20.5 cm.) long. The flowers aren’t particularly ornamental, but attractive, bright red berries replace them in the fall if a male plant grows nearby. The flowers and fruit often hide behind the foliage. Aucuba also makes nice container shrubs or houseplants. Read on to learn about the care of Aucuba japonica.
How to Grow Aucuba Shrubs
Aucuba plant care is easy if you select a good location. Here is a list of ideal aucuba growing conditions:
- Shade. Deeper shade means brighter leaf color. Plants tolerate partial shade, but leaves turn black if they get too much sun.
- Mild temperatures. Japanese aucuba plants survive winters in USDA plant hardiness zones 7b through 10.
- Well-drained soil. The ideal soil is moist with a high organic content, but the plants tolerate almost any soil, including heavy clay, as long as it is well-drained.
Plant the shrubs 2 to 3 feet (0.5-1 m.) apart. They grow slowly, and the area may look sparse for quite a while as they grow to fill their space. The advantage of slow growth is that the plant rarely needs pruning. Clean up plants as necessary by snipping off broken, dead, and diseased foliage and twigs.
Aucuba shrubs have moderate drought tolerance, but they grow best in moist soil. Water often enough to keep the soil moderately moist using cold water. Hot water from a hose that has been left in the sun can encourage disease. Spread a 2- or 3-inch (5-7.5 cm.) layer of mulch over the roots to help the soil hold moisture and prevent weeds.
Although they are rarely bothered by insects, you may occasionally see scales. Watch for the raised, tan spots on the leaves and stems. Scale insects leave deposits of sticky honeydew that become infested with black sooty mold. You can remove a few scale insects by scraping them off with a fingernail. Treat infestations by spraying the shrub with insecticidal soap or neem oil in early spring before the insects settle down to feed and develop their hard outer shells.
Note: Aucuba is toxic if eaten. Avoid planting aucuba in areas where children play.