How to Grow a Thick, Sturdy Trunk on a Radermachera sinica (China Doll)

Radermachera sinica (China Doll) is a tree species very well suited to being grown as a foliage houseplant. Placing it indoors in a ventilated, sunny spot not only brings a touch of greenery to the space and fills the environment with vitality, but also purifies indoor air so we can breathe fresher air. Overall, keeping a potted Radermachera sinica at home feels comfortable in every way. But as a potted plant, ornamental value is an important indicator of its worth. If the trunk of a potted Radermachera sinica is weak and spindly, its ornamental value is bound to be poor.

Normally, potted Radermachera sinica is more ornamental when it has lush branches and leaves, deep green glossy foliage, and an upright, thick, sturdy trunk. By comparison, getting a potted Radermachera sinica to grow lush branches and glossy green leaves is usually fairly easy to achieve, but getting the trunk to grow thick is much harder. So how do you grow a thick trunk on a Radermachera sinica? If we want to improve the ornamental value of a potted Radermachera sinica by thickening its trunk, we generally need to pay more attention to the details of care and management.

1. Remove the terminal buds

In its natural growing state, Radermachera sinica often grows a thin, tall trunk with relatively few side branches. This is because the plant's main growing points tend to be concentrated at the very top of the trunk, and when light and temperature are suitable and water and nutrients are sufficient, the plant concentrates its apical growth advantage and keeps growing upward for a long time. But once its main growing points are promptly cut off, the growing points are dispersed, and nutrients also flow back down to the lower part. This encourages the plant to sprout more side branches and at the same time achieves the effect of thickening the trunk.

2. Thin out the side branches

After the apical growth advantage of the potted Radermachera sinica is removed, as the growing points disperse, quite a few side branches will sprout from the trunk. At this point, besides maximizing water and nutrient management to maintain the sprouting and growth of the side branches, we also need to pinch the tips of overly vigorous side branches and remove their terminal growing points. Letting the excess nutrients continue to flow back into the stem of the Radermachera sinica means that as nutrients keep accumulating in the stem, the stem will grow thicker and sturdier.

3. Increase water and nutrients

While the main trunk of a potted Radermachera sinica is thickening, it often consumes a great deal of water and nutrients; only with sufficient water and nutrients can it support its rapid growth process. So from the time the trunk stops extending at the top, through the sprouting of side branches and the thinning of those side branches, and on to the thickening of the trunk, the whole process requires large amounts of water and nutrient consumption, so water and nutrient management must be done promptly throughout. Radermachera sinica itself also rather likes fertilizer and moisture, and only with sufficient water and nutrients can it maintain robust growth.

4. Repot and change the soil

As the stem of the Radermachera sinica keeps thickening while the space of the original pot is limited, we need to repot it and change the soil in time, creating a more suitable growing environment for it by enlarging the pot and increasing the amount of soil. This way, not only is there more ample space in the pot for the Radermachera sinica to spread out, but the greater volume of soil can also store more water and nutrients for it to absorb. This provides good hardware conditions for the trunk of the Radermachera sinica to keep thickening and for it to grow lush branches and leaves.

It can be seen that to grow a thick trunk on a potted Radermachera sinica, we need to combine pinching, pruning, water and nutrient management, and repotting in our care. Of course, these four aspects play the main role in promoting trunk thickening in potted Radermachera sinica, but we must not neglect the management of light, temperature and other factors either. It often takes the combined use of all these care measures to thicken the trunk quickly and achieve twice the result with half the effort.