Care for a China Doll Plant

A China doll plant (Radermachera sinica) can reach 30 feet tall when grown outdoors in U.S. Department of Agriculture plant hardiness zones 10 through 12. It also grows well as a houseplant in any climate, although it won't grow nearly as tall. China doll plants produce glossy, evergreen leaves, and fragrant white or yellow flowers when cared for properly.

China doll plants thrive in full sun, but they can tolerate partial shade in hot, sunny climates. Temperatures below 40 degrees Fahrenheit damage or kill China doll plants. Strong winds easily damage the plant so it's best to grow China doll in an area protected from the prevailing wind, such as near a fence or wall. Rich, well-drained soil that retains moisture well without becoming soggy encourages healthiest growth. Avoid areas with sandy soil that dry out quickly or heavy soil that tends to drain poorly and become waterlogged.

Regular watering so the soil never completely dries results in healthy growth. China doll plants don't tolerate drought. Water outdoor plants weekly if the top 1 to 2 inches of soil begin to dry. Providing the plants with about 1 inch of water weekly, from watering or rain, is usually enough to maintain proper soil moisture. A 2-inch layer of mulch over the soil further helps retain moisture. Apply a slow-release, balanced fertilizer, such as a 15-15-15 blend, every three months from spring through fall. Sprinkle 1 tablespoon of fertilizer over each 1 square foot of space surrounding the shrub, leaving 6 inches between the fertilizer and the trunk, and then water after application so the nutrients soak into the soil.

Although not necessary, pruning doesn't harm a China doll and helps it maintain a balanced shape. Before pruning, wipe the shears with a isopropyl alcohol-soaked rag to disinfect them. You can cut back any overgrown, damaged or dead branches to the desired height or to the nearest healthy wood, making the cut within 1/4 inch of a leaf or bud. Removal of branches that are crossed or rubbing prevents future damage and opens up the center of the shrub for air circulation. China doll plants tolerate pruning at any time without stress or damage.

Few pests or diseases affect China doll plants, except for aphids and root rot. Avoid root rot by planting in well-draining soil and watering properly. Aphids, which are soft-bodied, pear-shaped insects that primarily feed on the undersides of the leaves, can weaken foliage or spread disease to otherwise healthy plants. Rinsing the foliage with a strong spray of water dislodges small aphid populations. Mixing 2 tablespoons of insecticidal soap with 1 gallon of water and fully drenching infested leaves destroys larger aphid populations, although you may need to reapply the soap four to seven days later to ensure complete removal. Follow any package precautions, and wear waterproof gloves and eye protection, when applying insecticides.

China doll plants grown in pots as a houseplant don't reach the lofty heights of their outdoor counterparts. When growing China doll indoors, place it in a pot with bottom drainage and set it near a south-facing window or in another location where it receives all-day sun. Indoor plants require watering when the top 1 inch of soil feels dry. Water every two weeks with a balanced soluble fertilizer, diluted at the rate of 1/2 teaspoon per 1 gallon of water, or according to package instructions, when indoor temperatures are above 60 F. The plants may die back if you take them outdoors for summer and bring them indoors for winter, but they usually recover within a few weeks if you continue to water them and provide them with sufficient sun. Leaf drop can occur when the plant is moved, as it's very sensitive to moving from one location to another.