Q: I bought a China doll (Radermachera sinica) about six weeks ago. It lost a great many of its leaves at the beginning. I have it on a table near a sliding glass window where it gets bright light but no direct sun. It is doing much better but is still losing some leaves on the bottom of the plant. I water it when it is dry. I have it in a western exposure on the third floor, and I know it is very warm, but I have the plant back from the doors. I grow all kinds of plants successfully and would love to be successful with this beautiful plant.
– Sonia Flaum
A: China doll is one of the most elegant plants in the world. It has lacy and glossy leaves that are deep green in color. It is also known as the emerald tree, perhaps on account of its opulent, sparkling, gem-like mien. China doll is surprisingly hardy. Although it is native to the Philippines and is sold everywhere as an indoor, delicate, tropical plant, it has thrived in outdoor gardens in California as far north as San Jose.
In tropical settings, China doll puts on explosive growth, reaching its mature height of 30 feet in just a few years. In the Valley, it will probably stop growing at about 20 feet. Tropical plants placed in temperate, subtropical or Mediterranean zones such as the Valley simply do not get as large as they are genetically capable of growing.
As in the case of most tropical plants, China doll will grow in full sun to shade, depending on the microclimate.
China doll, if it is to succeed in our gardens, must be protected from hot sun. The most spectacular specimen I have seen was at the Los Angeles County Arboretum in Arcadia. The last time I visited it, which was several years ago, it was a luxurious, symmetrical specimen around 20 feet tall that faced the morning sun, but had its southern and western flanks protected by the foliage of other trees.
Getting back to your particular plant, Sonia, you may want to give it a bit more water since, at least when young, China doll prefers moist soil. Generally, tropical plants that can grow outdoors in the Valley develop a tolerance for dryness, but only as they mature. The Hawaiian elf (Schefflera arboricola) is the best example of this. This common indoor plant will grow into an outdoor garden lover’s 6-foot-tall by 6-foot-wide shrub with umbrella-shaped leaves in shade or partial sun. But it will require regular water until it nearly reaches this size when, at long last, it will require as little water as almost any other mature shrubs.
Actually, just like the coconut palm, which is also native to the Philippines, China doll prefers a wet, acidic and sandy soil. The fact that your plant has lost its lower leaves is not a sign of imminent death. Over the years, I have seen many plants go into shock and lose their lower leaves. On occasion, I have seen plants lose all their leaves. However, as long as the uppermost bud on the plant is fresh, it still has the capacity to make a full recovery. This is due, in part, to the fact that the hormones that make roots grow are produced in this uppermost bud and sent all the way down the length of the plant; as long as that apical bud is intact, new roots will continue to develop.
If you have a balcony, you may want to put down some newspaper there and change your soil. Regular potting soil tends to be heavier than that preferred by many indoor plants. Mix your potting soil with washed or construction-grade sand (available by the bag in home centers) to improve drainage.