Of the plants displayed for their foliage, the 'Capella' or 'Gold Capella' dwarf schefflera (Schefflera arboricola 'Gold Capella') is among the easiest to grow. A cultivar with green-and-yellow leaves, it's also called variegated Hawaiian elf schefflera. The plant grows well as a houseplant but also can thrive outdoors all year in U.S. Department of Agriculture plant hardiness zones 10 through 11. 'Gold Capella' needs only basic care and the right environment to flourish either indoors or in an outdoor garden.
Light and Water
The plant grows best outdoors in partial shade and also tolerates full shade, especially where summers are hot. A spot under tall trees that provide shifting shade throughout the day is a good location for 'Gold Capella,' as is a porch or patio where the plant gets some afternoon shade. Indoors, a 'Gold Capella' does best in bright indirect light, such as near a lightly curtained south- or west-facing window; it can also tolerate some direct sunlight on its leaves when it is grown indoors.
'Gold Capella' grows outdoors in any type of well-drained garden soil and does well as a houseplant when grown in commercial potting soil. Although this plant is quite drought-tolerant, it does best with regular watering. So water its soil whenever the top 1/2 inch of the soil feels dry to your fingertip. Water thoroughly, but allow a potted 'Gold Capella' to drain completely, and never leave its pot sitting in a water-filled saucer. If you grow 'Gold Capella' outdoors, lay 2 to 3 inches of organic mulch on the soil surface under its canopy to help conserve soil moisture, but keep the mulch a few inches from the plant's center to discourage the growth of fungus.
You can stimulate steady growth in this plant by fertilizing it monthly during the growing season, generally in spring and summer. For either a potted or garden-grown 'Gold Capella,' use a water-soluble, balanced fertilizer, such as a 20-20-20 formula, diluting it at a rate of 1/2 teaspoon in 1 gallon of water, but check your fertilizer's label for its specific directions. Use the fertilizer-water solution in place of a regular watering. During fall and winter, withhold fertilizer to give the plant a rest.
Size Control and Container Changes
A 'Gold Capella' plant naturally develops a shape considered pleasing, becoming about 10 feet tall when grown outdoors and somewhat smaller, usually up to about 8 feet tall, when grown as a houseplant. It doesn't require pruning, but you can cut it back to control its size, doing so in late winter or early spring when the plant is ready to put out new growth. Cut back stems to the length you desire, making each cut just above a leaf to keep the plant looking attractive after the pruning. Use sharp shears, wiping the blades with rubbing alcohol after each cut to prevent spreading plant diseases.
If you grow a 'Gold Capella' in a container and its roots or stems are getting crowded, you can repot it into a larger container in late winter, before its growth begins again. In its new pot, set the plant at the same soil depth at which it grew in its old pot, and ensure the new pot has at least one drainage hole in its bottom. Use any commercial potting soil or make your own mixture by combining 2 parts peat moss, 2 parts loam and 1 part sand. Tamp the soil well in the new pot, and water it.
The 'Gold Capella' is usually quite disease-resistant, whether grown outdoors or as a houseplant. A garden-grown specimen is also usually free of significant insect problems. When it is grown indoors, though, pests might infest the plant. These pests include scales -- hard-bodied, brown insects about 1/16 inch in diameter -- and spider mites, which aren't visible with the naked eye but leave behind visible webs on leaves and stems.
Control spider mites by spraying the plant with insecticidal soap, which is available in either a ready-to-use format or in a concentrated form that needs to be diluted with water. Dilute 5 tablespoons of a concentrated insecticidal soap in 1 gallon of water. Spray the spider mite-affected 'Gold Capella' with either ready-to-use or diluted insecticidal soap until the plant is dripping wet, and repeat the treatment every two weeks as needed. Spray on a windless day when the temperature isn't above 90 degrees Fahrenheit.
Hand-pick scale insects if you seen them on the plant, or, for a heavy infestation of scales, spray the plant with horticultural oil, diluted at a rate of 2 tablespoons per 1 gallon of water; repeat this treatment if the pests reappear. Spray on a windless day when the temperature is 90 F or lower, and, when mixing the horticultural oil or spraying it, wear glasses or goggles, gloves and other clothing that will protect your skin from the oil and oil mixture, which can cause irritation.